NONDESTRUCTIVE TESTING GLOSSARY I 533
flux indicator: A small device, generally a metal strip or foreign materials:They may appear as isolated, irregular
disk, containing artificial discontinuities. Used to deter-
or elongated variations of film density not correspond-
mine fwiehledndciroercrteicotnmhaagvneebtiezeinngaccohniedvietido.n6s and/or mag-
netic ing to variations in thickness of material or to cavities.
iMncalyudbeedsainndth, eslamga, toexriiadleboerindgroesxsammeintaeldo.3r any material
flux leakage: A local distortion of normal magnetic flux
patterns in a magnetized test object. Can be caused by forging crack: Discontinuity formed during mechanical
discontinuities in the test object." shaping of metal."
flux leakage field: The magnetic field that leaves or enters foundry: An establishment or building where metal cast-
the surface of an object.6J6
ings are produced.3
fluxleakage method:A method for the detection and anal-
fovea centralis: Region of sharpest vision in the retina,
ysis of a surface discontinuity or near-surface disconti-
where the layer of blood vessels, nerve fibers and cells
nuity using the flux that leaves a magnetically saturated, above the rods and cones is far thinner than in periph-
or nearly saturated, test object at a discontinuity.4·6 eral regions."
flux lines: See lines off orce.
flux method: See lumen method. foveal vision: See photopic vision.
flux meter: An electronic device for measuring magnetic fractography:Descriptive treatment of fracture, especially
flux.6 See also gauss meter. in metals, with specific reference to photographs of the
fracture surface. Macrofractography involves pho-
focal zone: The distance before and after the focal point in
tographs at low magnification, microfractography at
which the intensity differs a specified amount (usually 6 high magnification.2
dB) from the focal intensity. Also called depth offield or
depth off OCUS.7 fracture:A break, rupture or crack large enough to cause a
full or partial partition of a casting.2,3
focus: Position of a viewed object and a lens system relative frame:A complete raster scan projected on a video screen.
to one another to offer a distinct image of the object as
There are thirty frames per second in a standard video
seen through the lens system. See accommodation and
depth offield. a output. A frame may be comprised of two fields, each
focus, principal plane of: The single plane actually in displaying part of the total frame. See alsofield. a
Fraunhofer zone: See far field.
focus in a photographic scene. a
free carbon: The part of the total carbon in steel or cast
focused beam:A sound beam that converges to a cross sec-
tion smaller than that generated by a flat transducer. 7 iron that is present in the elemental form as graphite or
temper carbon.3
focused transducer:A transducer that produces a focused
frequency:The number of complete wave cycles passing a
sound beam.7 given point per second or the number of vibrations per
focusing, automatic: (1) Feature of camera, usually second.7 Measured in hertz (Hz).
incorporating a range finder, whereby the lens system frequency, fundamental: In resonance testing, the fre-
adjusts to focus on an object in part of the field of
quency at which the wavelength is twice the thickness
view. (2) Metaphorical attribute of a borescopic of the test material. 7.12
instrument's depth of field (the range of distance in frequency, pulse repetition: The number of pulses per
focus). The depth of field is so great in the case of second, in hertz (Hz).7
video borescopes that focusing is unnecessary for most frequency, test: The nominal ultrasonic wave test fre-
applications. a quency used in a test. 7.12
focusing, primary:Focusing of an image by the lens onto a Fresnel zone: See near field. Also called Fresnel field. 7
fiber optic bundle at the tip of a probe." fretting:Action that results in surface damage, especially in
focusing, secondary: Focusing at the eyepiece of a a corrosive environment, when there is low amplitude
borescope or other optical instrument, specifically the motion between solid surfaces in 2contact under pres-
sure. Also called fretting corrosion.
manual refocusing needed when the viewing distance
changes."
fretting corrosion:See corrosion, fretting.
foil: Metal in sheet form less than 0.15 mm (6 x 10-3 in.)
fretting wear: See wear, fretting.
thick.2
friction oxidation:See wear,fretting.
footcandle: Former unit of measure for illumination,
front surface: The first surface of a test object encoun-
equivalent to one lumen evenly distributed over a tered by the incident ultrasonic beam. See interface. 7
square foot or to a surface illumination at a distance of full-wave direct current: A single-phase or three-phase
one foot from a point of one candela. Abbreviated ftc or
alternating current rectified taonpdrofldowuc. e6 direct current
fc. See also lux.a characteristics of penetration
footlambert: Former unit of luminance. Measured in the
furring:Buildup or bristling of magnetic particles resulting
SI system by candela per square meter,"
from excessive magnetization of the test object.6·16
534 I NONDESTRUCTIVE TESTING OVERVIEW
G gauss meter: A magnetometer that registers field strength
in gauss (or Tesla).6
gage pressure: Pressure above ( or below if measured from
general examination: A test or examination of a person's
gage zero) atmospheric pressure at the measurement knowledge, typically (in the case of nondestructive test-
location.1 ing personnel qualification) a written test on the basic
principles of a nondestructive testing method and gen-
gaggers: The metal supports that reinforce sand in the eral knowledge of basic equipment used in the method.
(According to ASNT's guidelines, the general examina-
cope.3 tion should not address knowledge of specific equip-
ment, codes, standards and procedures pertaining to a
galling:A type of adhesive wear more gross than fretting. 8 particular application.) Compare practical examination
and specific examination. 8
galvanic series: List of metals, alloys and graphite (a non-
metal) in sequence with the most anodic (easiest cor-
roded) in liquids at one end and the most cathodic
(least easily corroded) at the other end.8
geometric moire techniques: Moire techniques that can
gamma iron: Iron with face centered cubic structure
be explained by geometric optics, mainly by the
formed by slow cooling of delta ferrite. This characteris- mechanical obstruction of light or the scalar addition of
tic lattice structure is stable between 906 °C (1,663 °F)
light.9
and 1,390 °C (2,.535 °F). Also called austenite.8
geometrical optics: The mathematical study of how light
gamma rays: High energy, short wavelength electromag-
netic radiation emitted by a nucleus. Energies of gamma rays are reflected and refracted and practical tech-
rays are usually between 0.01 and 10 MeV X-rays also niques based on such understanding, including the
occur in this energy range but are of non-nuclear origin. transmission of i8mages by lenses and mirrors. Also
called lens optics.
Gamma radiation usually accompanies alpha and beta
ghost: An indication arising from a combination of pulse
emissions and always accompanies fission. Gamma rays repetition frequency and time base frequency.18 See
wrap around. 7
are very penetrating and are best attenuated by dense
materials like lead and depleted uranium.'!
glare: Excessive brightness (or brightness varying by more
gas holes: Holes created by a gas evolving from molten than 10:1 within the ofbiesledrvoaftvioienwa)nwdhjuicdhgimnteenrfte. 8res with
metal.2 Appear as round or elongated, smooth edged clear vision, critical
dark spots, occurring individually, in clusters or dis- glare~ blinding: Glare so intense that for an appreciable
tributed throughout a casting.3 length of time after it has been removed, no object can
be seen.8·20
gas porosity: Gas pockets or voids in metal. Refers to
porous sections in metal that appear as round or elon- glare, direct: Glare resulting from high luminances or
gated dark spots corresponding to minute voids usually insufficiently shielded light sources in the field of ._
distributed through the entire casting.3 Spherical or view.8,20
elongated internal cavities caused by evolution of dis-
glare, reflected: Glare resulting from specular reflections
solved gasses from molten metal or slag trapped during
of high vluiemwin.8a·20nces in polished or glossy surfaces in the
cooling and solidification of castings or fusion welds.2 field of
gas tungsten arc welding (GTAW)I:nert gas shielded arc glosrsemfleetcetar:nceR. 8e·2f0lectometer used to measure specular
welding using a tungsten electrode. Also called tung
sten inert gas (TIC) welding.8
gooseneck: The pressure vessel or metal injection pump in
gasket seal: Resilient ring, usually virgin polytetrafluo- an air injection casting machine.3
roethylene (PTFE), in a piping or tubing connection. gouge: Surface indentation caused by forceful abrasion or
Compare interference sealing thread and metalto impact or flame cutting. Also called nick. Compare tool
metal seal. 8 mark.8
·
gate: (1) In ultrasonic testing, an electronic device for mon- grain boundary: Interface that forms between grains of
solidifying metal as the random oriented crystal lattices
itoring signals in a selected segment of the trace on an meet. See grain. 8
A-scan display. (2) The interval along the baseline that
is monitored." (3) In casting, the channel through which
molten metal enters a mold cavity. Sometimes called grain refiner: Any material, usually a metal from a special
group, added to a liquid metal or alloy to produce a
ingate.3 finer grain in the hardened metal.3
gated pattern: A pattern designed to include gating in the
mold.3
grain size: Size of the crystals in metal. When compared
gauss: A customary or cgs unit of flux density or magnetic with a standard, usually referred to as being fine,
induction. See tesla. 6 medium or coarse.2
NONDESTRUCTIVE TESTING GLOSSARY I 535
graininess: A film characteristic that consists of the group- halide: A compound of two or more elements, one of which
ing or clumping together of the countless small silver is a halogen.1
grains into relatively large masses visible to the naked
eye or with slight magnification.'! halitation: Rings of light visible around a spot on a video
screen where an electron scanning beam is held. 8
grains: (1) Solid particle or crystal of metal. As molten
metal solidifies grains grow and lattices intersect, form- Hall detector: A semiconductor element that produces an
ing irregular grain boundaries.8 (2) Individual crystals output electromotive force proportional to the product
that make up the crystalline structure of metal. 2 of the magnetic field intensity and a biasing current. 4
grass: See background noise. Hall effect: A potential difference developed across a con-
grating: A grid superimposed on an optical test surface to ductor at right angles to the direction of both the mag-
netic field and the electric current. Produced when a
measure displacement or deformation. See also refer current flows along a rectangular conductor subjected
ence grating.9 to a transverse magnetic field.6,15
gray: SI unit for measurement of absorbed radiation dose,
absorbed by matter at a particular location and halogen: Any of the nonmetallic elements - fluorine,
expressed in joules per kilogram (J-kg-1). Replaces the chlorine, bromine, and iodine - or any gaseous chemi-
rad. cal component containing one or more of these ele-
gray level: Integer number representing the brightness or ments.
darkness of a pixel or, as a composite value, of an image
comprised of pixels.8 halogen leak detector: A leak detector that responds to
graybody: Radiator whose spectral emissivityis uniform for halogen containing tracer gases. Normally not very sen-
all wavelengths but not 1.0. See blackbody.8 sitive to the elemental halogen gases, but are very good
green core: A sand casting core that has not been baked.3 when they are used with a gas that contains halogen.1
green rot: Form of attack due to simultaneous carburiza- Also called a halogen sensitive leak detector or a halide
tion and oxidation of stainless heating elements com- leak detector.1
mon to nickel chromium and nickel chromium iron
alloys, especially in furnace environments.8 halogen sniffer test: A pressure leak test in which the
green sand: Core sand intended for use in a damp state.3 leakage of a component, pressurized with a halogen
grid: In moire and grid nondestructive testing, cross hatch rich mixture, is detected by scanning over the test
pattern of two sets of parallel lines, one set of lines object boundary surface with a probe connected to a
being perpendicular to the other; the lines in each set halogen leak detector. Halogen gas is pulled from the
are parallel to each other and spaced at fixed intervals. leak through the probe inlet to the sensing element to
The term grid also refers to the physical or real cross cause a visible or audible signal on the indicator of the
line grating.9 leak test instrument.1
grinding cracks: Shallow cracks formed in the surface of
relatively hard materials because of excessive grinding halogen standard leak: A standard leak in which the con-
heat or the high sensitivity of the material. 2 Grinding tained gas is a halogen tracer gas compound.1
cracks typically are 90 degrees to the direction of grind-
ing.8,19 hardness: Resistance of metal to plastic deformation, usu-
ally by indentation. However, the term may also refer to
gross porosity: In weld metal or in a casting, pores, gas stiffness or temper or to resistance to scratching, abra-
holes or globular voids that are larger and in greater sion or cutting.2
number than obtained in good practice.2·3
harmonic: A vibration frequency that is an integral multi-
group velocity: The rate at which the envelope of an ultra- ple of the fundamental frequency.7,1o
sonic pulse (many frequencies) propagates through the
medium.7 harmonic analyzer: A mechanical device for measuring
the amplitude and phase of the various harmonic com-
growth: The expansion of a casting because of aging.3 ponents of a periodic function from its graph.4,14
H harmonic distortion: Nonlinear distortion characterized
by the appearance in the output of harmonics other
Had.field's steel: An austenitic manganese specialty steel than the fundamental component when the input wave
that is easily work hardened. 8 is sinusoidal.v'"
half-wave direct current: A single-phase alternating cur- hash: See background noise.
rent half-wave rectified to produce a pulsating unidi-
rectional field. Also called halfwave current.6,16 head shot: Producing circular magnetization by passing
current directly through the test object. Commonly
done while holding the object between the headstock
and tailstock of a wet horizontal magnetic particle test -
ing system.6
536 I NONDESTRUCTIVETESTING OVERVIEW
heading: Upsetting wire, rod or bar stock in dies to form horizontal linearity: In ultrasonic testing, a measure of
parts having some of the cross sectional area larger than the proportionality between the positions of the indica-
the original. Examples are bolts, rivets and screws.v!" tions appearing on the horizontal trace and the posi-
tions of their sources. 7
heads: The clamping contacts on stationary magnetic parti-
cle systems.w'? horn gate: A curved gate shaped like a horn and arranged
to permit entry of molten metal at the bottom of casting
heat: The energy associated with the random and chaotic cavity.3
motions of the atomic particles from which matter is
composed. All materials (hot or cold) contain heat and horseshoe coil:A probe coil in which the ferrite core of the
radiate infrared energy. The unit for measuring heat is coil is horseshoe shaped. Also called a U coil or Ucore
the joule (J), equal to about 0.24 calorie (cal) or coil.4
9.481 x 10-4 British thermal units (BTUs). Compare
infrared radiation and temperature. 9 horseshoe magnet: A bar magnet bent into the shape of a
horseshoe so that the two poles are adjacent. Usually
heat affected zone (HAZ):Base metal not melted during the term applies to a permanent magnet.6,1o
brazing, cutting or welding, but whose microstructure
and physical properties were altered by the heat. 2 hot cracks: Ragged dark lines of variable width and
numerous branches. They have no definite line of con-
heat checking: Surface cracking caused when metal tinuity and may exist in groups. They may originate
rapidly heated (or cooled and heated repeatedly) is pre- internally or at the surface.3 Cracks occurring in hot
vented from expanding freely by colder metal below solid metals, caused by stresses of thermal expansion
the surface. Friction may produce the heat. Sometimes or contraction and originating either internally or at
called thermal fatigue. 8 the surface.2
heat treatment: Heating and cooling a metal or alloy in hot thermionic ionization gage: Positive ion current
such a way as to obtain desired conditions or properties. flowing from a tungsten or thorium coated filament to
Heating for the sole purpose of working is excluded a cylindrical grid collector is proportional to gas den-
from the meaning of this definition.2·3 sity over the absolute pressure range below 100 mPa
(10-3 torr).
heat wave: Thermally produced variation in flue gas den-
sity that distorts images of objects in a firebox.s hot spot: The point of retarded solidification caused by an
increased mass of metal at the juncture of two sections.
helium leak detector: A leak detector that responds · to It frequently results in shrinka~e and inferior mechani-
· helium tracer gas.1 cal properties at this location.2·
helium mass spectrometer leak detector: Mass spec- hot tear: A fracture formed in a metal during solidification
trometer constructed to be peaked for response to because of hindered contraction. Surface cracks on
helium gas. castings produced by contraction of the metal during
cooling.2•3 Hot tears often occur where areas of differ-
hertz: The unit of frequency equivalent to one cycle per ent thickness adjoin. 8
second. 4.7,1o.14
hot working: Deforming metal plastically at temperature
high temperature penetrant: A penetrant material spe- and rate such that strain hardening does not occur. Low
cifically designed for use on high temperature surfaces temperature limit is recrystallization temperature.2
where conventional penetrant would be unsatisfactory.2
hue: Characteristic of light at a particular bandwidth that
hindered contraction.' Contraction where the geometry gives a color its name.f
will not permit a casting to contract in certain regions in
keeping with the coefficient of expansion of the metal hundred percent testing: See one hundred percent testing.
being cast.3
hydrogen embrittlement: A condition of low ductility in
holes: Any void remaining in an object as a result of metals resulting from the absorption of hydrogen.2
improper manufacturing processing. Often called gas
holes, cavities or air locks» hydrophilic emulsifier or remover: Water base materials
used for excess surface penetrant removal.2
homogenizing: Holding at high temperature to eliminate
or decrease chemical segregation by diffusion.2 hyperthermia: Heating so excessive that it can damage or
kill plant or animal cells.8
hood test: A quantitative leak test in which a test object
under vacuum test is enclosed by a hood filled with hysteresis: (1) The lagging of the magnetic effect when the
tracer gas so as to subject all parts of the test object to magnetizing force acting on a ferromagnetic hody is
examination for leakage at one time. A form of dynamic changed. (2) The phenomenon exhibited by a magnetic
leak testing in which the entire enclosure or a large por- system wherein its state is influenced by its previous
tion of its external surface is exposed to the tracer gas history."
while the interior is connected to a leak detector with
the objective of determining the existence of leakage.1
NONDESTRUCTIVE TESTING GLOSSARY I 537
hysteresis loop: A curve showing flux density B plotted as a impedance: The total opposition that a circuit presents to
function of magnetizing force H as magnetizing force is the flow of an alternating current, specifically the com-
increased to the saturation point in both negative and
positive directions sequentially. The curve forms a char- plex quotient of voltage divided by current.vP
acteristic S shaped loop. Intercepts of the loop with the
BH axis and points of minimum and maximum magne- impedance analysis:In electromagnetic testing, an analyt-
tizing force define important magnetic characteristics ical method that consists of correlating changes in the
of a matenal.v!"
amplitude, phase, quadrature components or all of
IACS: The International Annealed Copper Standard. A
conductivity measurement system in which the conduc- these, of a complex test signal voltage to the electro-
tivity of annealed, unalloyed copper is arbitrarily rated magnetic conditions within the test object.4.13
at 100 percent and the conductivities of other materials
are expressed as percentages of this standard.26 The impedance plane diagram: A graphical representation
% IACS is equivalent to 172 divided by the material (real part along the horizontal axis and imaginary part
resistivity in microohm centimeters.4
along the vertical axis) of the locus of points indicating
icicles: A coalescence of metal protruding beyond the root
of the weld. Sometimes called bum through. 2 the variations in the impedance of a test coil as a func-
tion of basic test parameters.v':'
ID coil: A coil or coil assembly used for electromagnetic
testing by insertion into the test piece, as with an inside impedance, acoustic: A mathematical quantity used in
probe for tubing. Also called inside coils or bobbin
coils. 4•13 computation of acoustic reflection and transmission
characteristics at boundaries. It is expressed as the
ideal gas: Gas that obeys the general gas laws for ideal product of wave velocity and density.1,21
gases. Also called perfectgas. 1
impregnation: (1) The treatment of porous castings with a
illuminance: The density of luminous flux on a surface. sealing medium to stop pressure leaks. (2) The process
Measured in the SI system by lux. 8
of filling the pores of a sintered compact, usually with a
illuminate: Shed light on.8
illumination: The act of illuminating or state of being illu- liquid such as a lubricant. (3) The process of mixing
particles of a nonmetallic substance in a matrix of metal
minated. See also illuminate. Compare illuminance.8,20
image: Visual representation of a test object or scene.8 powder, as in diamond impregnated tools.3
image enhancement: Any of a variety of image processing
impurities: Elements or compounds whose presence in a
steps, used singly or in combination to improve the material is unintentional.V'
detectability of objects in an image.8
image guide: Fiber bundle that carries the picture formed in control: Within prescribed limits of process control.8
by the objective lens at the distal end of a fiber optic
borescope back to the eyepiece.8 in-motion radiography: Technique in which either the
image orthicon: Television tube that uses the photoemis-
sion method. Compare vidicon tube.8 object being radiographed or the source of radiation is
image processing: Actions applied singly or in combina- in motion during the exposure.3,11
tion to an image, in particular the measurement and
alteration of image features by computer. Also called incanthdeermscaelnecxec:itaTthioen.e8mission of visible radiation due to
picture processing. 8
image quality indicator: Penetrameter. incandescent: Emitting visible radiation as a result ofheat-
image segmentation: Process in which the image is parti- ing.8
tioned into regions, each homogeneous.8
immersion technique: The ultrasonic technique in which inclusion: Foreign particles or impurities, usually oxides,
the test object and the transducer are submerged in a
liquid (usually water) that acts as the coupling sulfides, silicates and such, that are retained in metal
medium.12 The transducer is not usually in contact with (welds or castings) during solidification or that are
the test object."
formed by subsequent reaction of the solid metal.2,3
incomplete fusion: Fusion that is less than complete. Fail-
ure of weld metal to fuse completely with and bond to
the base metal or preceding bead. 2
incomplete penetration: In welding, root penetration that
is less than complete or failure of a root pass and a back-
ing pass to fuse with each other.2 Also called lack of
fusion.2
incremental permeability: The ratio of the change in
magnetic induction to the corresponding change in
magnetizing force when the mean induction differs
from zero.4,14
indication. A nondestructive testing discontinuity response
that requires interpretation to adnedteframlsine einditiscaretiloenv.a8nce.
Compare defect, discontinuity
indication, discontinuity: The visible evidence of a mate-
rial discontinuity. Subsequent interpretation is required
to determine the significance of an indication.2
538 I NONDESTRUCTIVE TESTING OVERVIEW
indication, false: An indication produced by something initial pulse: The electrical pulse applied to excite an ultra-
other than a discontinuity. Can arise from improper test sonic transducer. The first indication on the screen if
procedures.6 the sweep is undelayed. Also called the main bang. May
also refer to the acoustic pulse generated by the electri-
indication, nonrelevant: An indication due to misapplied cal pulse.7
or improper testing. May also be an indication caused
by an actual discontinuity that does not affect the inlet: The opening, flange, connection or coupling on a leak
usability of the object (a change of section, for detector or leak testing system through which tracer gas
instance). 2 may enter from a leak in a test object. I
indication, relevant: An indication from a discontinuity inserted coil: See ID coil. Also called inside coil. 4•13
(as opposed to a nonrelevant indication) requiring eval- insonification: Irradiation with sound.7
uation by a qualified inspector, typically with reference
to an acceptance standard, by virtue of the discontinu- inspection medium: See examination medium.
ity's size or location.8•22
inspection: See examination.
induced current technique: See current induction tech
nique. integrated leakage rate test (ILRT):The leakage test
performed for an entire system or component by pres-
induced magnetization: A magnetic field generated in an surizing the system to the calculated peak containment
object when no direct electrical contact is made.6.16 internal pressure related to the design and determining
the overall integrated leakage rate.1
induction: The magnetism produced in a ferromagnetic
body by some outside magnetizing force.6.1° intensity, radiant: The luminous flux per steradian ema-
nating from a visible source, measured in lm-sr'. Also,
inductor: A device consisting of one or more associated from a nonvisible source, the radiant flux per steradian
windings, with or without a magnetic core, for introduc- emanatingJrom that source and measured in W-sr-1.
ing inductance into an electric circuit or material.t-"
interface: The boundary between two adjacent media.7•10
inert gas: Gas that does not readily combine with other
substances. Examples are helium, neon and argon.I interface triggering: In ultrasonic testing, triggering the
sweep and auxiliary functions from an interface echo
inert gas shielded arc welding: Joining of metals by heat- occurring after the initial pulse. Also called IF synchro
ing them with an electric arc between the electrode(s) nization. 7
and the work piece, using an inert gas to shield the elec-
trode(s). See also gas tungsten arc welding.8 interference fitted thread: See interference sealing
thread.
infrared: Below red, referring to radiation of frequency
lower than the color red. See infrared radiation. 9 interference objective: Small, metallized glass mounted
in contact with the test object and adjustable for tilt to
infrared and thermal testing: Nondestructive testing that control fringe spacing.8
uses heat or infrared radiation as interrogating energy.
interference sealing thread: Piping seal using a tapered
infrared cameras: Radiometer that collects infrared radia- connection made under great pressure, forcing mating
tion to create an image.9 surfaces together more tightly than is possible by hand
alone. Compare gasket seal and metaltometal seal. 8
infrared radiation: Radiant energy below the color red, of
wavelengths longer than 770 nm, between the visible intergranular corrosion: Corrosion occurring preferen-
and microwave regions of the electromagnetic spec- tially at grain boundaries.2
trum. 8,9,20
intergranular stress corrosion cracking: An anomaly
infrared thermography: Imaging by infrared radiation. caused by intergranular corrosion as a result of sensi-
See infrared radiation. Compare thermography. 9 tized material, stress and corrosive environment (typi-
cal in the heat affected zone of stainless steel welds).
ingate: See gate.
interlaced scanning: A process whereby the picture
inherent discontinuities: Discontinuities that are pro- appearing on a video screen is divided into two parts.
duced in the material at the time it is formed (for exam- Interlaced scanning reduces flicker by increasing the
ple, during solidification from the molten state).2 electron beam's downward rate of travel so that every
other line is sent. When the bottom is reached, the
inherent fluorescence: Fluorescence that is an intrinsic beam is returned to the top and the alternate lines are
characteristic of a material. 6.16 sent. The odd and even line scans are each transmitted
at 1/60 s, totaling 1/30 s per frame and retaining the
initial permeability: The slope of the induction curve at standard rate of 30 frames per second. The eye's persis-
zero magnetizing force as the test object is removed tence of vision allows the odd and even lines to appear
from a demagnetizing condition (slope at the origin of as a single image without flicker.8
the BH curve before hysteresis is observedi.vl''
internal conductor: See central conductor.
NONDESTRUCTIVE TESTING GLOSSARY I 539
interpretation: The determination of the significance of J
test indications from the standpoint of their relevance Jaeger eye chart: An eye chart used for near vision acuity
examinations. 8
or irrelevance. The determination of the cause of an
joint: The part of the mold where the cope and cheek, cope
indication or the evaluation of the significance of dis- and drag or cheek and drag come together.3
continuities from the standpoint of whether they are joint efficiency: The strength of a welded joint expressed
detrimental or inconsequential. 2 as a percentage of the strength of the unwelded base
metalf
interstitial alloy: Alloy in which the atoms of the alloying
element fit into the spaces between the atoms of the joint penetration: The distance weld metal and fusion
parent metal.8 extend into a joint. 2
inverse segregation: Segregation in cast metal in which an K
excess of lower melting constituents occurs in the ear-
lier freezing portions, apparently the result of liquid Kaiser effect: The absence of detectable acoustic emission
metal entering cavities developed in the earlier solidi- until the previous maximum applied stress level has
fied metal.3 been exceeded.5
inverse square law: From a point source of radiation, the keeper: Ferromagnetic material placed across the poles of
intensity of energy arriving at a point of interest varies a permanent magnet to complete the magnetic circuit
as the inverse square of distance from source.3.11 and prevent loss of magnetism.6·15
investment casting: (1) Casting metal into a mold pro- kinetic vision acuity: Vision acuity with a moving target.
duced by surrounding (investing) an expendable pat- Studies indicate that 10 to 20 percent of visual effi-
tern with a refractory slurry that sets at room ciency can be lost by target movement.8
temperature after which the wax, plastic or frozen mer-
cury pattern is removed. Also called precision casting or L
lost wax process. (2) A casting made by the process.3
laboratory microscope: Conventional compound micro-
investment compound: A mixture of graded refractory scope. See microscope and microscope, compound.8
filler, a binder and a liquid vehicle, used to make molds
for investment castings.3 lack of fusion: Discontinuity due to lack of union between
weld metal and parent metal or between successive
investment molding: A method of molding by using a pat- weld beads.2 Also called incomplete penetration.
tern of wax, plastic or other material invested or sur-
rounded by a molding medium in slurry or liquid form. Lamb wave: A type of ultrasonic wave propagation in
After the molding medium has solidified, the pattern is which the wave is guided between two parallel surfaces
removed by subjecting the mold to heat. Also called lost of the test object. The mode and velocity depend on the
wax process or precision molding.3 product of the test frequency and the separation
between the surfaces. Also called plate waves. 7
ion current: The current that flows at all times from the
positive emitter (heater) to the negative cathode collec- lambertian: Having a surface that diffuses light uniformly
tor of the heated anode (alkali ion) halogen vapor rather than reflecting it. Matte. Most objects have a
detector. This current increases in the presence of halo- lambertian surface. Compare specular.8
genated gases.1
laminated pole pieces: See articulated pole pieces.
ionizing radiation: Any radiation that directly or indirectly lamination: Discontinuity in plate, sheet or strip caused by
displaces electrons from the outer domains of atoms.
Examples include alpha, beta and gamma radiation.'! pipe, inclusions or blowholes in the original ingot. After
rolling, laminations are usually flat and parallel to the
IQI: Image quality indicator. See penetrameter. outside surface. Laminations may also result from pipe,
blisters, seams, inclusions or segregation elongated and
IR: Infrared and thermal testing. are made directional by working. Lamination disconti-
nuities may also occur in metal powder compacts.2 May
iris: Ring of variable area around the pupil and in front of appear in the form of rectangles or plates as inclusion
the lens of the eye. The surface area of the iris adjusts stringers between rolled surfaces. Short, intermittent
spontaneously to change the amount of light entering laminations may be detrimental if the object is sub-
the eye.8 jected to high bending stresses in service.6
irradiance: Power of electromagnetic radiant energy inci-
dent on the surface of a given unit area. Compare radi
ance. 8
Ishihara™ plates: Trade name for a kind of pseudoisochro-
matic plates.8
isotropy: A condition in which significant medium properties
(velocity, for example) are the same in all directions.7
540 I NONDESTRUCTIVE TESTING OVERVIEW
lap: Surface discontinuity, usually parallel to the surface, liftoff effect: In an electromagnetic test system output, the
effect observed due to a change in magnetic coupling
appearing as a fold or tangential seam in a wrought between a test object and a probe coil whenever the
distance between them is varied.4,13
product and caused by folding over of a hot metal fin or
light: Radiant energy that can excite the retina and produce
sharp corner in a thin plate, then rolling or forging 2i•6t a visual sensation. The visible portion of the electro-
into the surface but not welding it. See also cold shut. magnetic spectrum, from about 380 to 770 nm.8,20
laser: An acronym (light amplification by stimulated emis light adapted vision: See photopic vision.
sion of radiation). The laser produces a highly mono- light guide bundle: Bundle of filaments, usually glass, that
chromatic and coherent (spatial and temporal) beam of carries noncoherent light from a high intensity source
through a fiber optic borescope to illuminate the
radiation. A steady oscillation of nearly a single electro- object.8
magnetic mode is maintained in a volume of an active light metal: One of the low density metals such as alu-
minum, magnesium, titanium, beryllium or their
material bounded by highly reflecting surfaces, called a alloys.2
resonator. The frequency of oscillation varies according lighting, back: Placement of light source and image sensor
to the material used and by the methods of initially on opposite sides of the test object, used when the sil-
houette of a feature is important.8
exciting or pumping the material.V"
lighting, flash: See lighting, strobe.
leak: An opening that allows the passage of a fluid.1,27
lighting, front:Placement of light source and image sensor
leak detector: A device for detecting, locating, and/or on the sameside of the test object.8
measuring leakage.1 lighting, strobe: Lighting that flashes intermittently at a
rate that may be adjusted and is often perceived as a
leak testing (LT):Nondestructive testing method for detect- flicker, used to image moving objects or still objects
with potential movement. 8
ing, locating or measuring leaks or leakage in pressurized
or evacuated systems or components.1 lighting, structured: Combining a light source with opti-
cal elements to form a line or sheet of light.8
leakage: The measurable quantity of fluid escaping from a
limited certification:Individuals who are certified only for
leak.1 specific operations are usually called limited Level (I, II
or III) or are designated as having limited certification
leakage design basis accident: The calculated peak con- because they are not qualified to perform the full range
of activities expected of personnel at that level of quali-
tainment internal pressure related to the design basis fication."
accident.1 line pair: Pair of adjacent, parallel lines used to evaluate
the resolution of a specific imaging system. See also
leakage field: See magnetic leakagefield. minimum line pair.8
leakage flux: Magnetic flux of the coil that does not link
linearity, amplitude: A measure of the proportionality of
with the test object. The magnetic flux that leaves a sat- the signal input to the receiver and the amplitude of the
signal appearing on the display of an ultrasonic instru-
urated or nearly saturated object at a discontinuity.4 ment or on an auxiliary display.7,23,24
leakage rate: The quantity of leakage fluid per unit time linearity,area:In ultrasonic testing, constant proportional-
ity between the signal amplitude and the areas of equal
that flows through a leak at a given temperature as a discontinuities located at the same depth in the far
result of a specified pressure difference across the field. Necessarily limited by the size of the ultrasonic
leak.1 See throughput. beam and configuration of the reflector.7
leaker penetrant: A penetrant especially designed for leak lines of force: A conceptual representation of magnetic flux
based on the line pattern produced when iron filings are
detection. 2 sprinkled on paper laid over a permanent magnet.6,16
leeches: Permanent magnets or electromagnets attached to lipophilic removers: An oil base material that disperses
into a penetrant through solvent action, creating a mix-
electrodes carrying magnetizing current, to provide ture that is emulsifiable in water, facilitating its removal
strong electrode contact.6,16 by a water wash.2
lens: Translucent object that refracts light passing through
it in order to focus the light on a target."
lens optics: See geometrical optics.
level, acceptance: In contrast to rejection level, test level
above or below which, depending on the test parame-
ter, test objects are acceptable.2
level, rejection: The value established for a test signal
above or below which, depending on the test parame-
ter, test objects are rejectable or otherwise distin-
guished from the remaining objects.2 See level,
acceptance.
lifting power: The ability of a magnet to lift a piece of fer-
ritic steel by magnetic attraction alone.6,15
liftoff: Distance between the probe coil and the test
object.4
NONDESTRUCTIVE TESTING GLOSSARY I 541
liquid crystals: Cholesteric liquids whose optical proper- luminous efficacy:The ratio of the total luminous flux of a
ties cause them to reflect vivid spectral colors for tem- light source to the total radiant flux or to the power
perature changes. Their adjustable response is sensitive input. Sometimes called luminous efficiency.8
and can be made to change from red to blue over a tem-
perature gradient as small as 1 °C (1.8 °F).9 luminous efficiency: See luminous efficacy.
luminous flux: Radiant energy's time rate of flow. Mea-
liquid penetrant: See penetrant.
liquid penetrant testing (PT): Nondestructive testing sured in lumens.8
luminous intensity: Luminous flux on a surface normal to
method using penetrant.
the direction from its light source, divided by the solid
location plot: A representation of acoustic emission angle the surface subtends at the source. Measured in
sources computed using an array of transducers.5 candela. Also known as candlepower.8
lux: Unit of measure for illuminance in SI. Equivalent to
logarithmic decrement: The natural logarithm of the lumens per square meter and symbolized lx. Formerly
ratio of the amplitudes of two successive cycles in a known as metercandle. 8
damped wave train. 7
M
longitudinal direction:The principal direction of flow in a
worked metal.2 machine vision: Automated system function of acquiring,
processing and analyzing images to evaluate a test object
longitudinal magnetic field: A magnetic field wherein or to provide information for human interpretation. A
the flux lines traverse the component in a direction typical system consists of a light source, a video camera,
essentially parallel with its longitudinal axis.6,16 a video digitizer, a computer and an image display.8
longitudinal magnetization: Magnetization in which the macroshrinkage: A casting discontinuity, detectable at
flux lines traverse the component in a direction essen- magnifications not exceeding ten diameters, consisting
tially parallel to its longitudinal axis.6.15 of.voids in the form of stringers shorter than shrinkage
cracks. This discontinuity results from contraction dur-
longitudinal wave: See compressional wave. 7 ing solidification where there is not an adequate oppor-
tunity to supply filler material to compensate for the
loose piece: A core positioned near, but not fastened to, a shrinkage. It is usually associated with abrupt changes
die and arranged to be ejected with the casting. The in section size.2•3
loose piece may be removed and used repeatedly for
the same purpose. Also, it is similarly used in or on pat- macrostructure:The structure of metals as revealed by
terns, core boxes and permanent molds.3 examination of the etched surface of a polished object
at a magnification not exceeding ten diameters.2
loss of back reflection:Absence or significant reduction of
an indication from the back surface of the test object.7·10 macular lutae: Irregular, diffuse ring of yellow pigment
which partly overlaps the fovea and surrounds it to
lost-waxprocess:An investment casting process in which a around 10 degrees and which absorbs blue light, thus
wax pattern is used.3 changing the color of the light reaching receptors
beneath."
lot tolerance percent defective: In quality control, the
percent defective at which there is a 10 percent proba- magnetic circuit: The closed path followed by any group
bility of acceptance in a production run.f of magnetic flux lines.6.15
low pass filtering: A linear combination of pixel values to magnetic field: Space in which the magnetic force is
smoothen abrupt transitions in a digital image. Also exerted within and surrounding a magnetized object.v!?
called smoothing. 8
magnetic field indicator:A device used to locate or deter-
LOX-safe penetrant: A penetrant material or system mine relative intensity of a flux leakage field.6.16
specifically designed to be compatible with or nonreac-
tive in the presence of liquid oxygen.2 magnetic field leakage: Seeflux leakagefield.
magnetic field strength: The measured intensity of a
LT: Leak testing.
magnetic field at a specific point. Expressed in amperes
lumen: Luminous flux per steradian from a source whose per meter or oersted.6
luminous intensity is 1 candela. Symbolized lm.8 magnetic flow technique: Closing the magnetic circuit of
an electromagnet with a test object or portion of it.
lumen method: A lighting design procedure used for pre- Resulting field is longitudinal in direction.f See longitu
determining the relation between the number and dinal magnetization.
types of lamps or luminaires, the room characteristics magnetic flux:The total number of lines of magnetic force
and the average illuminance on the work plane. It takes existing in a magnetic circuit.5.15
into account both direct and reflected flux. Also called
flux method. 8·20
luminance: The ratio of a surface's luminous intensity in a
given direction to a unit of projected area. Measured in
candela per square meter.8
luminosity:The luminous efficiency of radiant energy.8
542 I NONDESTRUCTIVETESTING OVERVIEW
magnetic flux density:The normal magnetic flux per unit manipulator:In immersion testing, a device for angular ori-
area. Expressed in tesla or gauss.5.15 entations of the transducer.7·21
magnetic flux leakage: Seeflux leakagefield. manometer: Instrument, usually a U shaped tube contain-
magnetic leakage field: Seeflux leakagefield. ing water or mercury, for measuring pressure (or pres-
magnetic leakage flux: Exiting of magnetic lines of force sure differentials) of gases and vapors. The difference
in liquid column height in the two vertical arms of the
from the surface of a test object.4·14 U-tube indicates the pressure difference.1
magnetic particle test system: Equipment providing the
manual zero: A control on a test instrument that allows the
electric current and magnetic flux necessary for mag- user to zero the instrument panel meter.1
netic particle discontinuity detectionP-P
magnetic particle testing (MT): A nondestructive test markers:In ultrasonic testing, a series of indications on the
method using magnetic leakage fields and indicating horizontal trace of a display screen that show increments
materials to disclose surface and near surface disconti- of time or distance.7·21
nuities.6.16
martensite: (1) Acicular (needlelike) microstructure pro-
magnetic particles: Finely divided ferromagnetic material duced by fast cooling or quenching of metals and alloys
capable of being individually magnetized and attracted such as steel. (2) The hard steel with such microstruc-
to flux leakage fields.6·16
ture produced by fast cooling of austenite.8
magnetic permeability: See permeability. mask: ( 1) A spatial filter in the sensing unit of a surface
magnetic powder: Magnetic particles in dry or powder
inspection system. (2) Ann x n square matrix with dif-
form with size and shape suitable for discontinuity ferent values that serves as a filter in image processing.8
masking:The covering of a portion of a test object so as to
detection.6·15 prevent tracer gas from entering leaks that may exist in
magnetic rubber: A specially formulated testing medium the covered section.1
mass spectrometer leak detector: Mass spectrometer
containing magnetic particles. Used to obtain replica with design factors optimized to produce an instrument
castings of component surfaces with discontinuities that has high sensitivity to a single tracer gas.1
being reproduced within the replica.6.15 match bend effect: Optical illusion whereby an area of
magnetic saturation:That degree of magnetization where a uniform brightness appears to be nonuniform because
further increase in magnetizing force produces no signif- of contrast with the brightness of an adjacent area.8
icant increase in magnetic fluxdensity in an object.4.13 match plate pattern:A sand molding pattern partly on the
magnetic writing: A nonrelevant indication sometimes cope side and partly on the drag side of the plate that
caused when the surface of a magnetized object comes forms the parting between the cope and drag sections
in contact with another piece of ferromagnetic material of the molding flask. Permanent forms for runners,
gates, sprue and riser locations and sometimes com-
or a current carrying cable.6·16 plete risers, are included. Such a pattern usually is
magnetism: (1) The ability of a magnet to attract or repel made of aluminum and is used extensivelywith molding
machines.3
another magnet or to attract a ferromagnetic material. match plate: A plate of metal or other material on which
(2) A force field surrounding conductors carrying elec- patterns for metal castings are mounted or formed as an
tric current.6·17 integral part so as to facilitate the molding operation.
magnetization: The process by which elementary mag- The pattern is divided along its parting plane by the
netic domains of a material are aligned predominantly plate.'
in one direction.6 material noise: Random signals caused by the material
magnetizing current:The electric current passed through structure of the test object.!" A component of back-
or adjacent to an object that gives rise to a designated
magnetic field.6 ground noise.7
magnetizing force: The magnetizing field strength applied material, ferromagnetic:A material that exhibits the phe-
to a ferromagnetic material to produce magneusm.P-'"
magnetometer: A device for measuring the strength of nomena of magnetic hysteresis and saturation and
magnets or magnetic fields.6·17 whose magnetic permeability is dependent on the mag-
magnitude:The absolute value of a complex number with- netizing force.2
out reference to the phase of the quantity.4 material, nonferromagnetic:A material that is not mag-
mallteicadbeilfiotrym:Tathioenchianraccotmerpisretiscsioofnmweittahlosutthartuppteurrme.it2s plas- netizable and not responsive to magnetic field tests.2
malleable cast iron: A cast iron made by a prolonged mathematical morphology: Image processing technique
anneal of white cast iron in which decarburization or of expanding and shrinking. The basic operators in
graphitization or both, take place to eliminate some or mathematical morphology are dilation (expanding),
all of the cementite. The graphite is in the form of tem- erosion (shrinking), opening and closing.8
per carbon.3
NONDESTRUCTIVE TESTING GLOSSARY I 543
matte: Tending to diffuse light rather than reflect it; not metallurgy:The science and technology of metals.2
shiny. Also called lambertian. The term matte is gener-
ally applied to smooth surfaces or coatings. Compare micro:A prefix that divides a basic unit of measure by one
specular.8 million.2
maximumburst amplitude:The maximum signal ampli- microhorescope:See borescope, micro.
tude within the duration of the burst. 5
microfissure:A crack of microscopic proportions.2
Maxwell'sequations:The fundamental equations of macro-
scopic electromagnetic field theory.4.14 micrograph:A graphic reproduction of the surface of a
prepared object, usually etched, at a magnification
mean free path: Average distance a gas molecule travels greater than ten diameters. If produced by photo-
between successive collisions with other molecules in graphic means it is called a photomicrograph (not a
the gas or vapor state.1 microphotograph). 2
measurement system: The entire system from sensor to microporosity: Porosity visible only with the aid of a
display inclusive.1 microscope. 2
mechanical properties: The properties of a material that microscope: An instrument that provides enlarged images
reveal its elastic and inelastic behavior where force is of very small objects.8
applied, thereby indicating its suitability for mechanical
applications (for example, modulus of elasticity, tensile microscope, compound: Conventional microscope, using
strength, elongation, hardness and fatigue limit).2 geometrical optics for magnification. Also called labo
ratory microscope. 8
melting point coatings: Coatings that melt at some spe-
cific temperature. Anomalies are usually associated microscope, interference: Magnifier using the wave-
with a temperature increase, so the materials melt first length of light as a unit of measure for surface contour
over anomalies. Melting point compounds also are and other characteristics.8
comparatively insensitive and require relatively high
surface temperatures.9 microscope, metallographic: Metallurgical microscope
designed for both visual observation and photomicrog-
meniscus method: A convex glass lens placed in contact raphy of prepared surfaces of opaque materials at mag-
with an optically flat glass platen. A dyed liquid nifications ranging from about 25 to about 3,000
between lens and platen forms a meniscus shaped film diameters.2 Also called a metallograph.
of liquid. This film has zero thickness at the central
point of contact between lens and platen. A nonfluores- microscope, metallurgical: Microscope designed with
cent or colorless spot appears at this point of contact, features suited for metallography.8
the spot diameter being a function of a dye constant
and dye concentration. 2 microscope, phase contrast:Laboratory microscope with
two additional optical elements to transmit both
mesopic vision: Vision adapted to a level of light between diffracted and undiffracted light, revealing refractive
photopic at 3.4 x 10-2 cd-rrr-' (3.2 x 10--3 cd,fr2) and index discontinuities in a completely transparent test
scotopic at 3 x 10-5 cd-m=' (2.7 x 10-6 cd,ft-2).8 object.8
metal-to-metal seal: Piping seal in which the mating sur- microscope, polarizing: Microscope with polarizing ele-
faces on the external connection (the pin) and internal ments to restrict light vibration to a single plane for
connection (the box) are machined to provide a pres- studying material with directional optical properties. As
sured interference fit 360 degrees around the connec- fibers, crystals, sheet plastic and materials under strain
tion. Compare gasket seal and interference sealing are rotated between crossed polarizers on the micro-
thread.8 scope stage, they change color and intensity in a way
that is related to their directional properties.8
metallic discontinuity: A break in the continuity of the
metal of an object. May be located on the surface (e.g., microscopic stresses: Residual stresses that vary from ten-
a crack) or deep in the interior of the object (e.g., gas sion to compression in a distance (presumably approxi-
pocket).2 mating the grain size) that is small compared to the
gage length in ordinary strain measurement. Hence,
metallograph:Short term for metallographic microscope. 8 not detectable by dissection method. Can sometimes
metallographic microscope: See microscope, metallo be measured by X-ray shift.2
graphic. microsegregations: (1) Segregation within a grain, crystal
or small particle. Also called coring.2 (2) Extremely nar-
metallography:The science dealing with the constitution row cracks, usually long and straight, on the surfaces of
and structure of metals and alloys as revealed by the highly finished wrought metals. Often very shallow,
unaided eye or by such tools as low powered magnifica- their identity must be established to ensure that the
tions, optical microscope, electron microscope and indications are not from detrimental cracks, deep laps
X-ray diffraction.2 or long inclusion stringers.6
metallurgical microscope:See microscope, metallurgical.
544 I NONDESTRUCTIVE TESTING OVERVIEW
microshrinkage:A casting discontinuity, not detectable at mold: A form or cavity into which molten metal is poured
magnifications lower than ten diameters, consisting of to produce a desired shape. Molds may be made of
interdendritic voids. This discontinuity results from sand, plaster or metal and frequently require the use of
contraction during solidification where there is not an cores and inserts for special applications.2•3
adequate opportunity to supply filler material to com- mold jacket: Wood or metal form that is slipped over a
pensate for shrinkage. Alloys with a wide solidification sand mold for support during pouring.3
temperature range are particularly susceptible.2•3
microstructure: The structure of polished and etched mold wash:An aqueous or alcohol emulsion or suspension
metal as revealed by a microscope at a magnification of various materials used to coat the surface of a mold
greater than ten diameters.2 cavity.3
microwave testing: Nondestructive testing method that
uses, for its probing energy, electromagnetic radiation molding machine: A machine for making sand molds by
of frequencies from 0.3 to 300 GHz, with wavelengths mechanically compacting sand around a pattern.3
from 1 mm to 1 m.4
miniature angle beam block:A specific type of reference molecular flow: Phenomenon occuring when mean free
standard used primarily for angle beam, but also for path length of gas molecules is greater than the largest
straight beam and surface wave calibration.7.12 cross sectional dimension of a leak or the tube through
miniature borescope: See borescope, miniature. which flow is occurring. 1
miniborescope:Jargon for miniature borescope. a
minimum line pair: The closest distance that a specificimag- molecule: A group- of atoms held together by chemical
ing system can resolve between a pair of adjacent, parallel forces. The atoms in the molecule may be identical (H2
lines (line pair) used to evaluate system resolution." and Sa) or different(H20 and C02).2
misrun: A casting not fully formed, resulting from the
metal solidifying before the mold is filled.3 monochromatic light: Light from a very small portion of
MKSA: A system of units for mechanics and electromagnet- the visible spectrum."
ics in which the basic units are meter, kilogram, second
and ampere. It is a constituent part of the SI system of monochromator: Device that uses prisms or gratings to
units.4.14 separate or disperse the wavelengths of the spectrum
into noncontinuous lines or bands."
mode: The manner in which an acoustic wave is propa-
gated, as characterized by the particle motion in the mottle: An apparently random positioning of metallic flakes
wave (shear, Lamb, surface or longitudinal).7,10 that creates an accidental pattern."
mode conversion: A change of ultrasonic wave propaga- MT: Magnetic particle testing.
tion mode upon reflection or refraction at an interface.7
multiaxialstresses: Any stress state in which two or three
mode of vibration:Type of wave motion. Three common principal stresses are not zero.2
modes used in ultrasonic testing are longitudinal, trans-
multidirectionalfield: A periodic magnetic field that pro-
verse and surface wave.7•21 duces magnetization in two or more mutually perpen-
model, analytical:A representation of a process or phe- dicular directions during a single cycle.6
nomenon by a set of solvable equations.v'" multidirectional magnetization: Two or more magnetic
modulus of elasticity:The ratio between stress and strain fields in different directions imposed on a test object
sequentially and in rapid succession.6·15
in a material deformed within its elastic range."
modulus of rupture: Nominal stress at fracture in a bend multifrequency:Two or more frequencies applied sequen-
tially or simultaneously (as in a pulse).4
test or torsion test. 2
multifrequency technique: Utilization of the response of
moire: Optical patterns caused by the beating of two a test object to more than one frequency, usually to sep-
superimposed gratings. Moire fringes usually appear arate effects that would be indistinguishable at a single
as alternating bright and dark bands on the image of frequency.4
the specimen. The gratings can be real or virtual. For
analysis of in-plane deformations, a deformed speci- multiparameter:The many parameters of a test system.
men grating and an undeformed reference grating are These parameters often affect test response and can
superimposed.9 often be distinguished with a multifrequency technique.4
moire interferometry: All moire techniques that require multiphasealloy:Alloyin which several phases are present."
physical optics for their explanation, particularly
diffraction and interference oflight waves. It is known multiple back reflections: In ultrasonic testing, repetitive
by other names, including interferometric moire, high echoes from the far boundary of the test object. 7,10
sensitivity moire and diffraction moire. 9
multivariable:See multiparameter.
mutual inductance:The common property of two electri-
cal circuits whereby an electromotive force is induced in
one circuit by a change of current in the other circuit.4.14
NONDESTRUCTIVE TESTING GLOSSARY I 545
N node: A point in a standing wave where a given characteris-
tic of the wave field has zero amplitude. 7
narrroanwgeboafnfdreeqdu:enAcyrerleastpivoenstee.r7m,12 denoting a restricted
NDC: Nondestructive characterization. nodular cast iron: A cast iron that has been treated while
NDE: (1) Nondestructive evaluation. (2) Nondestructive molten with a master alloy containing an element such
as magnesium or cerium to give primary graphite in the
examination.8 spherultic form.3
NDI: Nondestructive inspection.8
NDT:Nondestructive testing. 8 noise: Any undesired signals that tend to interfere with nor-
near field: The distance immediately in front of a trans- mal reception or processing of a desired signal. The ori-
gin may be an electrical or acoustic source, small
ducer in which the ultrasonic beam exhibits complex discontinuities or abrupt changes in properties of the
and changing wavefronts. Also called the Fresnel field test material. 7•12
or Fresnel zone. 7•10
near surface discontinuity:A discontinuity not open to nondestructivecharacterization (NDC):Branch of non-
but near the surface of a test object. Produces broad, destructive testing concerned with the description and
fuzzy,lightly held dry magnetic particle indications.6·16 prediction of material properties and behaviors of com-
near ultraviolet radiation: Ultraviolet radiation with ponents and systems.
wavelengths ranging from about 320 to about 400 nm -.
Sometimes called black light.8 nondestructive evaluation (NDE): Another term for
near vision:Vision of objects nearby, generally within arm's nondestructive testing. In research and academic com-
length. Compare far vision. 8 munities, the word evaluation is often preferred
nearsightedness: Vision acuity functionally adequate for because it emphasizes interpretation by knowledgeable
viewing objects nearby, generally within arm's length personnel.8
but not at greater distances. Also called myopia. Com-
pare farsightedness. 8 nondestructive examination (NDE): Another term for
necking down: Localized reduction in area of a specimen nondestructive testing. In the utilities and nuclear
or structural member during welding or overloading.s,19 industry, examination is sometimes preferred because
negative sliding:The rolling and sliding of meshing gears testing can imply performance trials of pressure con-
or rollers when the rolling and sliding are in opposite tainment or power generation systems.8
directions.8
neper: The natural logarithm of a ratio of two amplitudes nondestructive inspection (NDI): Another term for non
(equal to 8.686 dB) used as a measure of attenuation. destructive testing. In some industries (utilities, avia-
Power ratios are expressed as half the natural logarithm.7 tion), the word inspection often implies maintenance
neural acuity:The ability of the eye and brain together to for a component that has been in service.8
discriminate patterns from background. Discrimination
is influenced by knowledge of the target pattern, by the nondestructive testing (NDT):The determination of the
scanning technique and by the figure/ground relation- physical condition of an object without affecting that
ship of a discontinuity.8 object's ability to fulfill its intended function. Nonde-
neutron: An uncharged elementary particle with a mass structive testing techniques typically use a probing
nearly equal to that of the proton. The isolated neutron energy form to determine material properties or to
is unstable and decays with a half-life of about 13 min- indicate the presence of material discontinuities (sur-
utes into an electron, proton and neutrino.!' face, internal or concealed). See also nondestructive
neutron radiography:Radiographic nondestructive test- evaluation, nondestructive examination and nonde
ing using neutrons as the interrogating particles. structive inspection. 8
nick: Surface indentation caused by forceful abrasion or
impact. Also called gouge. Compare tool mark. 8 nonferromagneticmaterial:A material that is not magne-
nit: A former unit for measuring luminance, equivalent to tizable and essentially not affected by magnetic fields.
one candela per square meter. Abbreviated nt.8 Includes paramagnetic materials and diamagnetic mate-
noble metals: Cathodic metals (such as gold, platinum and rials. 4,13
silver), which strongly resist corrosion.8
nodal points: In angle beam ultrasonic testing, the location nonrelevant indication:See indication, nonrelevant.
of reflections at opposite surfaces as a wave progresses
along a test object.7 normal incidence: ( 1) A condition in which the axis of an
ultrasonic beam is perpendicular to the entry surface of
the test object. (2) A condition where the angle of inci-
dence is zero.7
normal induction:The maximum induction in a magnetic
material that is symmetrically and cyclically magne-
tized. 4,14
normalpermeability:The ratio of normal induction to the
corresponding maximum magnetizing force. In aniso-
tropic media, normal permeability becomes a matrix. 4,14
546 I NONDESTRUCTIVE TESTING OVERVIEW
normalized impedance diagram: In electromagnetic organoleptic: Relying on or using sense organs, such as the
testing, an impedance curve from which the effects of human eye.8
frequency on a probe in air have been removed. Usually
the plotted data are ( 1) the measured reactance divided orientation: The angular relationship of a surface, plane,
by the reactance of the coil in air versus (2) the mea- discontinuity or axis to a reference plane or surface.U?
sured resistance less the resistance in air divided by the
coil reactance in air.4 orthicon: See image orthicon.
oscillogram:Common term for a record or photograph of
normalizing:Heating a ferrous alloy to a suitable tempera-
ture above the transformation range and then cooling in data displayed on the cathode ray tube face.7J2
air to a temJ?erature substantially below the transforma- ounces per year (oz/yr): Units defining the size of a leak
tion range.
as the weight of refrigerant gas that will pass through
NR: Neutron radiographic testing. the leak in one year.1
null: To adjust a bridge circuit so that the test sample and outgassing: Forms of gas coming from material in a vac-
uum system. Includes gases adsorbed on the surface,
reference arms produce equal and opposite currents dissolved in material, trapped in pockets and those due
through the detector. 4 to evaporation or condensation.1
null signal: A fixed component of a test coil signal that is overall integrated leakage rate: The total leakage
subtracted from the output signal leaving only that part through all leakage paths including containment welds,
of the signal that varies with test object conditions.4 valves, fittings and components that penetrate a pri-
numerical analysis:A technique to generate numbers as mary reactor containment system, expressed in weight
the solution to a mathematical model of a physical sys- percent of contained air mass per day.1
tem. Used in place of a closed form analytic expression.
Usually requires digital computation. 4 p
0 pancake coil: A probe coil whose axis is normal to the sur-
face of the test material and whose length is not larger
objective: In discussion of a lens system (camera, than the radius.4
borescope, microscope, telescope), of or pertaining to
the end or lens closest to the object of examination - parafoveal vision: See scotopic vision.
at the end opposite from the eyepiece. Distal; tip.8 parallax:The apparent difference in position of an imaged
OCTG:Oil country tubular goods.8 point according to two differently positioned sensors.8
oersted: The cgs unit of magnetic field strength, abbrevi- parallel magnetization:A magnetic field induced in mag-
ated Oe. In air, 1 Oe = 1 gauss. Replaced by Si's ampere netizable material placed parallel to a conductor carry-
per meter. 6·15 ing an electric current.l? Not a recommended practice
oil country tubular goods (OCTG):Hollow cylindrical for magnetic particle testing.6
components used to convey petroleum and related paramagnetic material: In electromagnetic testing, a
products.8 material that has a relative permeability slightly greater
one hundred percent testing: Testing of all parts of an than unity and is practically independent of the magne-
entire production lot in a prescribed manner. Some- tizing force.4•13
times, complete testing entails the testing of only the parameter distribution:A display of the number of times
critical portions of the part. Compare sampling, partial. 8 the acoustic emission parameter falls between the val-
open sand casting:Any casting made in a mold that has no ues x and x + 8x as a function of x. T~ical parameters
cope or other covering.3 are amplitude, rise time and duration.
opening: Image processing operation of erosion followed parasitic echo: See spurious echo.
by dilation. A single opening eliminates isolated single particle motion: Movement of particles of material during
pixels. See also closing.8 wave propagation.7
opsin: See visual purple. parting line: The mark left on the casting where the die
optic disk:Area in the retina through which the fibers from halves meet. Also, the surface between the cover and
the various receptors cross the inner (vitreous humor) ejector portions of the die.3
side of the retina and pass through it together in the optic parting sand: Fine sand for dusting on sand mold surfaces
nerve bundle. This transitional area is completely blind." that are to be separated. 3
optimum frequency: The frequency that provides the parts per million (ppm):Concentration of a specific gas in
highest signal-to-noise ratio compatible with the detec- another gas or gas mixture. For example, a tracer gas
tion of a specific discontinuity. Each combination of concentration might be 10 ppm in air or nitrogen. The
discontinuity type and material may have a different more specific term µUL is often used, with ppm to
optimum frequency.7•12 indicate proportion by volume.1
NONDESTRUCTIVE TESTING GLOSSARY I 547
pass: In welding, a single bead along the entire weld length penetration time: The time allowed, after penetrant has
or the process of laying down that bead. 8 been applied to a surface, for the penetrant to enter dis-
continuities that may be present. The length of time
pattern: A form of wood, metal or other material, around elapsing between the application of the penetrant to
which a molding material is placed to make a mold for the test object and the removal of the penetrant. 2
casting metals.3
penetration, ultrasonic: Propagation of ultrasonic energy
pearlite: Platelet mixture of cementite and ferrite in steels into a material. See also effective penetration. 7
or in alpha and beta phases in nonferrous alloys.8
period: The absolute value of the minimum interval after
peeling: (1) The dropping away of sand from the casting which the same characteristics of a periodic waveform
during shakeout. (2) The detaching of one layer of a or a periodic feature retum.v'"
coating from another or from the basic metal, because
of poor adherence.3 peripheral vision: The seeing of objects displaced from
the primary line of sight and outside the central visual
pencil source: An artificial source using the fracture of a field.8•20
brittle graphite lead in a suitable fitting to simulate an
acoustic emission event. 5 permanent magnet: An object possessing the ability to
retain an applied magnetic field for a long period of
penetrability: The condition of being penetrable so that time after the active power of the field has been
liquid can enter into very fine openings such as cracks. removed. 6.1°
Often erroneously used to describe the property of a
penetrant that causes it to find its way into very fine permanent mold: A metal mold of two or more parts used
openings.2 repeatedly for the production of many castings of the
same form.3
penetrameter: A strip of metal the same composition as
that of the metal being tested, representing a percent- permeability: (1)A general term for various relationships
age of object thickness and provided with a combina- between magnetic induction and magnetizing force.
tion of steps, holes or slot or alternatively made as a These relationships are: (a) absolute permeability (the
wire. When placed in the path of the rays, its image quotient of a change in magnetic induction divided by
provides a check on the radiographic technique the corresponding change in magnetizing force) or
employed+!' Also called image quality indicator. (b) specific (relative) permeability (a pure number that
is the same in all unit systems). The value and dimen-
penetrant: A liquid capable of entering discontinuities sion of absolute permeability depend on the system of
open to the test surface and that is adapted to the pene- units employed. In anisotropic media, permeability
trant test process by being made highly visible in small becomes a matrix.4·14 (2) The characteristic of materials
traces. Fluorescent penetrants fluoresce brightly under that allows gases or liquids to pass through them.3
ultraviolet light and visible penetrants are intensely col- (3) The ratio of flux density B to magnetizing field
ored to be readily visible on developer backgrounds strength H. High permeability materials are easier to
when illuminated with visible light.2 magnetize than low permeability materials.6
penetrant comparator: See comparator, penetrant. phantom: A reference standard used to verify the perfor-
mance of ultrasound systems.7
penetrant leak testing: A technique of penetrant testing
in which the penetrant is applied to one surface of a test phase: In metallurgy, a physically homogeneous portion of
material while the opposite surface is tested for indica- a material system, specifically the portion of an alloy
tions that would identify a through leak or void passing characterized by its microstructure at a particular tem-
through the material thickness.2 perature during melting or solidification.8
penetrant testing: Nondestructive testing method using phase analysis:An analytical technique that discriminates
penetrant. between variables in an object undergoing electromag-
netic testing by the different phase angle changes that
penetrant, fluorescent: A penetrant characterized by its these conditions ~roduce in the test signal. See also
ability to fluoresce when excited by ultraviolet light.2 phase detection. 4.1
penetrant, post emulsifiable: A penetrant that requires phase angle: The angular equivalent of the time displace-
the application of a separate emulsifier to render the ment between corresponding points on two sine waves
excess surface penetrant water washable.2 of the same frequency.4,13
penetrant, visible:A penetrant characterized by an intense phase contrast microscope: See microscope, phase con
visible color dye that allowsit to give contrasting indica- trast.
tions on a white developer background.2
phase detection: The derivation of a signal whose ampli-
penetrant, water washable: A penetrant with built in tude is a function of the phase angle between two alter-
emulsifier that makes it directly water washable.2 nating currents, one of which is used as a reference.v'"
548 I NONDESTRUCTIVETESTING OVERVIEW
phase diagram:Graph showing the temperature, pressure picture processing: See image processing.
and composition limits of phase fields in a material sys-
tem. Also called a constitution diagram. Compare equi piezoelectric effect: The ability of certain materials to
librium diagram. 8 convert electrical energy into mechanical energy and
vice versa.7·12
phase shift: A change in the phase relationship between
two alternating quantities of the same frequency.4·13 pinhole porosity: Porosity, in either castings or metal
formed by electrodeposition, resulting from numerous
phase velocity: The velocity of a single frequency continu- small holes distributed throughout the metal.3
ous wave.7
pipe: (1) The central cavity formed during solidification of
phase-sensitive system: A system whose output signal is metal, especially ingots, by thermal contraction. (2) The
dependent on the phase relationship between the volt- discontinuity in wrought or cast products resulting from
age returned from a pickup or sensing coil and a refer- such a cavity. (3) An extrusion discontinuity due to the
ence voltage.4•13 oxidized surface of the billet flowing toward the center
of the rod at the back end. (4) A cast, wrought or
phased array:A mosaic of transducer elements in which welded metal tube.2
the timing of the elements' excitation can be individu-
ally controlled to produce certain desired effects, such pitch and catch:Test technique in which ultrasonic energy
as steering the beam axis or focusing the beam.7 is emitted by one transducer and received by another on
the same or opposite surface.12 Also called pitchcatch,
phasor quantity:Any quantity that is expressed as a com- two transducer technique or dual crystal method. 7
plex number. See impedance. 4·15
pitting: Discontinuity consisting of surface cavities. See
photoconduction: Method by which a vidicon television also cavitation fatigue and pittingf atigue.8
camera tube produces an electrical image, in which con-
ductivity of the photosensitive surface changes in rela- pitting fatigue: Discontinuity consisting of surface cavities
tion to intensity of the light reflected from the scene typically due to fatigue and abrasion of contacting sur-
focused onto the surface. Compare photoemission.8 faces undergoing compressive loading. See also cavita
tion fatigue and pitting. 8
photoelasticity:The effect of a material's elastic properties
on the way that it refracts or reflects light.8 pixel: A lighted point on the screen of a digital image. Pic-
ture element. 8
photoelectric effect: Emission of electrons from a surface
bombarded by sufficiently energetic photons. Such Planck'sDistribution Law:The distribution criterion for
emissions may be used in an illuminance meter and blackbody radiation.
may be calibrated in lux. 8,20
plane of focus: Seefocus, principal plane of
photoemission: Method by which an image orthicon tele-
vision camera tube produces an electrical image, in plane wave: A wave in which points of same phase lie on
which a photosensitive surface emits electrons when parallel plane surfaces.7.18
light reflected from a viewed object is focused on that
surface. Compare photoconduction. 8 plaster molding: Molding where a gypsum bonded aggre-
gate flour in the form of a water slurry is poured over a
photometer: The basic measuring instrument of photome- pattern, permitted to harden and is thoroughly dried
try. Accurate meters measuring radiant energy incident after removal of the pattern. The technique is used to
on a receiver, producing measurable electrical quanti- make smooth nonferrous castings of accurate size.3
ties."
plastic deformation:Deformation that does or will remain
photometric brightness:The luminance of a light source.8 permanent after removal of the load that caused it.2
photometry:The science and practice of the measurement
plate wave: See Lamb wave.
of light or photon-emitting electromagnetic radiation. platelet: Flat crystallites in certain phases of steel.8
See also relative photometry.8
photon: Particle of light.8 plunger machines:Die casting machines having a plunger
photopic vision: Vision adapted to daylight and mediated in continuous contact with molten metal.3
mainly by the cones. Visionis wholly photopic when the
luminance of the test surface is above 0.034 cd-m-2 point of incidence: In ultrasonic testing, the point at
(0.0032 cd-ft+). Also known as foveal vision and light which the center of the sound beam leaves the plastic
wedge of an angle beam transducer and enters the test
adapted vision. Compare mesopic vision and scotopic object.12 See probe index. 7
vision. 8·20
photoreceptor: Light sensor.8 polarizing microscope: See microscope, polarizing.
physical properties: Nonmechanical properties such as
density, electrical conductivity, heat conductivity and pole: See magnetic pole.
thermal expansion. 2 poling: The process of reorienting crystal domains in cer-
picture element: See pixel. tain materials by applying a strong electric field at ele-
vated temperatures. Materials (usually ceramics) so
treated exhibit piezoelectric behavior.7
NONDESTRUCTIVE TESTING GLOSSARY I 549
pores: (1) Small voids within a metal. (2) Minute cavities, probe: In leak testing, the physical means for sensing a
sometimes intentional, in a powder metallurgy comf act. gaseous leak, typically a tube having a fine opening at
(3) Minute perforations in an electroplated coating. one end, used for directing or collecting a stream of
tracer gas. Detector probes are used for pressure testing
porosity: A discontinuity in metal resulting from the cre- and tracer probes are used for vacuum testing.1 In ultra-
ation or coalescence of gas. Very small pores are called sonic testing, see search unit. 7
pinholes.U?
probe coil: In electromagnetic testing, a· small coil or coil
positive sliding: The rolling and sliding of meshing gears assembly that is placed on or near the surface of test
or rollers when directions of rolling and sliding are the
same.8 objects.4·13
probe coil clearance: The perpendicular distance between
postcleaning: The removal of penetrant testing residues
from the test piece after penetrant test processing is adjacent surfaces of the probe and test object. See lift
completed.2 off. 4.13
postemulsification: A penetrant removal technique probe gas: A tracer gas that issues from a fine orifice so as
employing a separate emulsifier applied over the sur- to impinge on a restricted (small) test area.1
face penetrant to make it removable with water spray.2
probe index: The point on a shear wave or surface wave
poultice corrosion: See corrosion, poultice. transducer through which the emergent beam axis
passes.I-"
pouring basin: A basin on top of a mold to receive the
molten metal before it enters the sprue or downgate.3 process: Repeatable sequence of actions to bring about a
desired result.8
pouring: Transferring molten metal from a furnace or a
ladle to a mold.3 process control: Application of quality control principles
to the management of a repeated process.8
powder: See dry powder.
process testing: Initial product testing to establish correct
powder blower: A compressed air device used to apply dry manufacturing procedures and then by periodic tests to
magnetic particles over the surface of a test object.6,16 ensure that the process continues to operate correctly.2
practical examination: In certification of nondestructive prod magnetization: See current flow technique.
testing personnel, a hands-on examination using test prods: Handheld electrodes for transmitting magnetizing
equipment and sample test objects. Compare general
examination and specific examination. 8 current from a generating source to a test object.6·15
production string: See tubing string.
precleaning: The removal of surface contamination or propagation: Advancement of a wave through a
smeared metal from the test piece so that it cannot
interfere with the penetrant testing process.2 medium.f-'"
pressure testing:. A technique of leak testing objects pres- proportioning probe: A probe that can vary the tracer gas
surized with a tracer gas with the subsequent detection concentration in the sample at the sensor, typically by
and location of any existing leaks with a sampling probe mixing pure air with sample gas from the probe inlet
(a qualitative test). Tests performed by increasing the port. Ratios of mixture between 100 percent pure air
pressure inside a test boundary to a level greater than (obtained from an outdoors source or by filtering ambi-
the surrounding atmosphere and detecting leakage by ent air through charcoal) and 100 percent leak sample
systematic examination of the outside of the test sur- gas are attainable without great changes in total flow
face. Leaks are located at time of detection; however, it from the probe. The proportioning probe used in halo-
is impossible to accurately determine a total leakage gen leak testing lets the user operate in an atmosphere
rate for the object being tested.1 with up to 1,000 µUL (ppm) tracer gas background
contamination. It proportions the amount of atmo-
prewash technique: Penetrant system in which major por- sphere allowed to enter the probe with its own (recircu-
tion of a nonwater washable penetrant is removed with
a water spray prior to application of the remover.2 lating) fresh air supply.1
pseudocolor: Image enhancement technique wherein colors
primary creep: First stage of creep, marked by elastic
strain plus plastic strain.8 are assigned to an image at several gray scale intervals.8
pseudoisochromatic plates: Color plates used for color
primary radiation: Radiation emitting directly from the
target of an X-ray tube or from a radioactive source.'! vision examinations. Each plate bears an image which
may be difficult for the examinee to see if his or her
primary reference response level: The ultrasonic color vision is impaired. 8
response from the basic calibration reflector at the psychophysics: Interaction between vision performance
specified sound path distance, electronically adjusted to and physical or psychological factors. One example is
a specified percentage of full screen height. 7 the so-called vigilance decrement, the degradation of
reliability based on performing visual and/or repetitive
principal plane of focus: Seefocus, principal plane of activities over a period of time. 8
550 I NONDESTRUCTIVE TESTING OVERVIEW
PT: Liquid penetrant testing. qualification: Process of demonstrating that an individual
pull cracks: In a casting, cracks caused by residual stresses has the required amount and the required type of train-
ing, experience, knowledge and capabilities. See also
produced by cooling because of the object shape.3 qualified. 8
pulse: A transient electrical or ultrasonic signal that has a
qualified: Having demonstrated the required amount and
rapid increase in amplitude to its maximum value, fol- the required type of training, experience, knowledge
lowed by an immediate return. 7·21 An example is the and abilities. See also qualification.8
signal that has propagated from the source to the trans-
ducer as detected using a flat response transducer. 5 quality: The ability of a process or product to meet specifi-
pulse echo method: An ultrasonic test method in which cations or to meet the expectations of its users in terms
discontinuities are detected by return echoes of the of efficiency, appearance, longevity and ergonomics.8
transmitted pulses.7
pulse length: A measure of ~ulse duration expressed in quality assurance: Administrative actions that specify,
time or number of cycles.7· 1 enforce and verify a quality program.8
pulse magnetization: Direct or indirect application of a
high field intensity, usually by the capacitor discharge quality control: Physical and administrative actions re-
method.6 quired to ensure compliance with the quality assurance
pulse method: Multifrequency technique in which a program. May include nondestructive testing in the
broadband excitation such as an impulse is used. Either manufacturing cycle. 8
the frequency components are extracted and analyzed
or the interpretation is based directly on characteristics quality of lighting: Level of distribution of luminance in a
of the time domain waveform.4 visual task or environment. 8
pulse repetition frequency: See repetition rate.
pulse tuning: Control of pulse frequency to optimize sys- quartz Bourdon tube gage: High precision pressure mea-
tem response.7 suring instrument containing a quartz helical Bourdon
pulser transducer: In acoustic emission testing, a trans- tube.!
ducer used as an artificial source of acoustic energy.5
pupil: Aperture in the center of an eye's iris, through which quasilongitudinal wave: A wave in which the direction of
light focused by the lens passes.8 particle motion is not parallel to the direction of energy
pure air supply: In leak testing, air that has been cleaned propagation. 7
of halogen contamination by means of an activated
charcoal filter. This term is sometimes also used to quasishear wave:A wave in which the direction of particle
describe any nonreactive gas, such as nitrogen, that motion is not perpendicular to the direction of energy
contains no halogen contamination and to which the propagation. 7
leak detector is not sensitive.1
purple: See visual purple. quenching of fluorescence: The extinction of fluores-
pyrometry: Type of radiation thermometer, giving readings cence by causes other than removal of the ultraviolet
for one point at a time, rather than imaging a scene in light (the exciting radiation).2
the manner of an infrared video camera. The word
pyrometry means fire measurement. As the name quick break: A sudden interruption of magnetizing cur-
implies, pyrometers are used for hot applications, such rent. Used in magnetic particle tests for materials with
as the monitoring of furnace or foundry conditions. high residual longitudinal magnetism and limited to
Pyrometers today are digital devices with liquid crystal three-phase fullwave rectified alternating current.6•16
temperature readouts. They may be mounted in place
or available as hand held units.9 R
Q rad: Radiation absorbed dose. A unit of absorbed dose of
Q of a coil: Ratio of reactance to resistance measured at the i1o0n-i5zJin(g1r0a0dieartgios)n.oOf rnaediraatdioins equal to the absorption of
operating frequency. 4,14 energy per gram of mat-
ter.11 Replaced by the gray ( Gy).
quadrature: The relation between two periodic functions radiance: Radiant flux per unit solid angle and per unit
when the phase difference between them is one-fourth
of a period.4.14 projected area of the source. Measured in watts per
square meter steradian. Compare irradiance. 8
radiant energy: Energy transmitted through a medium by
electromagnetic waves. Also known as radiation. 8
radiant flux: Radiant energy's rate of flow, measured in
watts.8
radiant intensity: Electromagnetic energy emitted per
unit time per unit solid angle. Measured in watts per
steradian.8
radiant power: Total radiant energy emitted per unit time.8
NONDESTRUCTIVE TESTING GLOSSARY I 551
radiation safety officer: An individual engaged in the rat's tooth principle: ( 1) The tendency for hard material
practice of providing radiation protection. The repre- on a tooth's front surface to wear more slowly than soft
sentative appointed by the licensee for liaison with the material on the back surface, keeping the edge sharp.
(2) Mechanism of wear whereby adjacent hard and soft
fapplicable regulatory agency.11 surfaces wear at different rates, producing a self sharp-
ening edge.8
radio frequency display:The resentation of unrectified
signals on a display screen . .12 Also called RF display. Rayleigh wave: An ultrasonic wave that propagates along
See also video presentation. the surface of a test object. The particle motion is ellip-
tical in a plane perpendicular to the surface, decreasing
radiographic interpretation: The determination of the rapidly with depth below the surface. The effective
cause and significance of subsurface discontinuities depth of penetration is considered to be about one
indicated on a radiograph. The evaluation as to the wavelength. 7
acceptability or rejectability of the material is based on
the judicious application of the radiographic specifica- real grating: In moire and grid nondestructive testing, a
tions and standards governing the material.'! physical grating on glass or other substrate. Two types
are the amplitude grating ( or bar-and-space grating)
radiographicscreens: Metallic or fluorescent sheets used consisting of opaque bars and clear spaces for use with
to intensify the radiation effect on films.!' transmitted light, or reflective bars and nonreflective
spaces for use with reflected light; and the phase grat
radiographic testing (RT):The use of radiant energy in ing consisting of an array of furrows on the surface of a
the form of X-rays or gamma rays for nondestructive transparent or opaque body.9
testing of opaque objects in order to produce graphical
records on a medium that indicates the comparative recarburize:( 1) To increase the carbon content of molten
soundness of the object being tested.'! cast iron or steel by adding carbonaceous material, high
carbon pig iron or a high carbon alloy. (2) To carburize
radiography:Radiographic testing. a metal object to return surface carbon lost in process-
radiology: That branch of medicine which uses ionizing ing. 3
radiation for diagnosis and therapy+' receiver: The section of an ultrasonic instrument that
radiometer: Instrument for measuring radiant power of amplifies echoes returning from the test object. Also, a
transducer that picks up the echoes.7
specified frequencies. Different radiometers exist for
different frequencies. 8 recommended practice: A set of guidelines or recom-
radiometricphotometer: Radiometer for measuring radi- mendations.f
ant power over a variety of wavelengths.8
radioscopy: A radiographic testing technique in which Recommended Practice SNT-TC-lA: See ASNT Recom
gamma rays or X-rays are used to produce an instanta- mended Practice No. SNTTClA.
neous image on a video or screen display as opposed to
a latent image on a film. The test object may be recovery: Reduced stress level and increased ductility of
remotely manipulated in real time to present a moving metal after work hardening. See creep. 8
radiographic image.
ramoff: A casting discontinuity resulting from the move- recovery time: The time required for a test system to
ment of sand away from the pattern because of return to its original state after it has received a sig-
improper ramming. 3 nal.4.13
range: In ultrasonic testing, the maximum path length that
is displayed. See also sweep length. 7.12 recrystallization:(1) The change from one grain structure
to another, as occurs on heating or cooling through a
rarefaction: The thinning or separation of particles in a critical temperature. (2) The formation of a new, strain
propagating medium due to the relaxation phase of an free grain structure from that existing in cold worked
ultrasonic cycle. Opposite of compression. A compres- metal, usually accomplished by heating. 2
sional wave is composed of alternating compressions
and rarefactions.U" rectified alternating current: A unidirectional electric
current obtained by rectifying alternating current with-
raster:A repetitive pattern whereby a directed element (a out the deliberate addition of smoothing to remove the
robotic arm or a flying dot on a video screen) follows inherent ripples.6.15
the path of a series of adjacent parallel lines, taking red mud: Debris (usually oxides of the contacting metals)
them successively in turn, always in the same direction of fretting wear, mixed with oil or grease and retained at
(from top to bottom or from left to right), stopping at or near the site of its formation. See also cocoa.8
the end of one line and beginning again at the start of
the next line. Following a raster pattern makes it possi- reference blocks: A block of material containing artificial
ble for electron beams to form video pictures or frames or actual cracks of various depths and widths used for
and for a sensor bearing armature to cover a predeter- reference in defining the size and location of defective
mined part of the surface of a test object. 8 areas in materials.2
552 I NONDESTRUCTIVE TESTING OVERVIEW
reference coil: In electromagnetic testing, the section of reinforcement of weld: (1) In a butt joint, weld metal on
the coil assembly that excites or detects the electromag- the face of the weld that extends out beyond a surface
netic field in the reference standard of a comparative plane common to the members being welded. (2) In a
system.vP fillet weld, weld metal that contributes to convexity.
(3) In a flash, upset or gas pressure weld, weld metal
reference grating: In moire and grid nondestructive test- exceeding base metal diameter or thickness.2
ing, an undeformed grating superimposed upon a spec-
imen grating to create the moire.P reject:An instrument function or control used for minimiz-
ing or eliminating low amplitude signals (electrical or
reference number: Number associated with the imped- material noise) so that other signals may be further
ance of a coil adjacent to a test sample.4 amplified. Use of this control can reduce vertical linear-
ity. Also called suppression. 7.12
reference standard:A typical test object with known arti-
ficial or natural discontinuities of various specific sizes, rejection level: See level, rejection.
relative permeability:The ratio of the permeability of the
used as a basis for test comparisons, equipment calibra-
tion or determining the efficiency of the discontinuity material to the permeability of vacuum. See permeabil
ity.4
detection process. Also called reference or pteiesct ep. 2anSeele, relative photometry: ( 1) Evaluation of a desired photo-
reference or test block and reference or test metric characteristic based on an assumed lumen out-
put of a test lamp. (2) Measurement of an uncalibrated
also acceptance standard. light source relative to another uncalibrated light
source.8
reference threshold: A preset voltage level that has to be relaxation:Relief of stress by creep. Diminishing stress by
exceeded before an acoustic emission signal is detected creep at constant strain frequently occurs in service.2
and processed. This threshold may be adjustable, fixed relay amplifier: An optional electronic module in some
or floating.5 heated anode (alkali ion) halogen vapor detector sys-
tems that amplifies the leak signal and initiates an auto-
reflectance: The Aralstiookonforwefnleacsterdeflwecatviveietyn.e8rgy to incident matic control. The control then either sounds an
wave energy. audible alarm, flashes a signal light, stops a conveyor or
operates whatever other control actuator the user con-
reflection: A general term for the process by which the nects to this relay output signal.1
incident flux leaves a surface or medium from the inci- relevant indication: See indication, relevant.
dent side, without change in frequency. Reflection is rem: Roentgen equivalent man. A unit of absorbed radia-
usually a combination of specular and diffuse reflec- tion dose in biological matter. It is equal to the
tion.8·20 absorbed dose in rads multiplied by the relative biolog-
ical effectiveness of the radiation.'!
reflection probe: A coil system that utilizes both an excita- remanent magnetism: See residual magnetic field.
tion and a detection or sensing coil on the same side of remote viewing:Viewing of a test object not in the viewer's
the sample.4 immediate presence. The word remote previously
implied either closed circuit television or fiber optic
reflectometer: Photometer used to measure diffuse, spec- systems remote enough so that, for example, the eye-
ular and total reflectance.8 piece and the objective lens could be in different
rooms. High resolution video and digital signals can
reflector: (1) In optical nondestructive testing, device used now be transmitted around the world with little loss of
to redirect the luminous flux from a source by the pro- image quality. Compare direct viewing. 8
cess of reflection.V"(2) Inultrasonic testing, a disconti- repeatability:Ability to reproduce a detectable indication
in separate processings and tests from a constant
nuity or object surface from which acoustic energy
returns to the sensor. source.1·2
repetition rate: The number of pulses generated or trans-
refracted beam: A beam that occurs in the second
medium when an ultrasonic beam is incident at an mitted per unit of time (usually seconds).7
acute angle on the interface between two media having replica: Piece of malleable material, such as polyvinyl or
different sound velocities.l-l''
polystyrene plastic film, molded to a test surface for the
refraction: The change in direction of a wave as a beam recording or analysis of the surface microstructure.8
passes from one medium into another having a differ-
ent sound velocity.A change in direction and mode may replication:A method for copying the topography of a sur-
occur at any angle of incidence. At small angles of inci- face by making its impression in a plastic or malleable
dence, the original mode and a converted mode may material.8
exist in the second medium.7
refractive index: The ratio of the velocity of an incident
wave to that of a refracted wave. It is known as the
refractive index of the second medium with respect to
the first.7
NONDESTRUCTIVE TESTING GLOSSARY I 553
reserve vision acuity: The ability of an individual to main- response factor: The response of the halogen leak detec-
tain vision acuity under poor viewing conditions. A tor to 3 x 10-7 Pa-m3-s-1 (3 x 10-6 std cm3-s-1) of tracer
visual system with 20/20 near vision acuity under R-12 or less, divided by the response to the same quan-
degraded viewing conditions has considerable reserve tity of another tracer gas. Thus, the actual leakage rate
vision acuity compared to that of an individual with of a detected leak will equal the indication of the detec-
20/70 near vision acuity.8 tor multiplied by the response factor of the specific
halogen tracer gas used. The response factor of a mix-
residual elements: Elements present in an alloy in small ture. of tracer and nontracer gases will be the response
quantities, but not added intentionally.2 factor of the tracer divided by the fraction of tracer gas
in the test gas (by volume) .1
residual magnetic field: The magnetism remaining in a
ferromagnetic material after the magnetizing force is response function: The ratio of response to excitation,
reduced to zero.5.1o both expressed as functions of the complex fre-
quency.4.14
residual method: Using the residual magnetic field of high
retentivity materials to trap magnetic particles and indi- retentivity:A material's property of retaining residual mag-
cate discontinuities. 6 netism to a greater or lesser degree.6•10
residual technique: Ferromagnetic particles are applied retina:In the eye, the tissue that senses light.8
to a test object after the magnetizing force has been dis-
continued. 6 retinene: See visual purple.
resolution: An aspect of image quality pertaining to a sys- RF display:See radiofrequency display.
tem's ability to reproduce objects, often measured by
resolving a pair of adjacent objects or parallel lines. See rhodopsin:See visual purple.
also minimum line pair and resolving power.8
ring standard:See test ring.
resolution, discontinuity:The property of a test system
that enables the separation of indications due to discon- ringdowncount: See acoustic emission count.
tinuities located in close proximity to each other in a
test object.2 ringing method: A test method for bonded structures in
which disbands are indicated by increased amplitude of
resolution test: Procedure wherein a line is detected to ringing signals.7.12
verify a system's sensitivity.8
ringing signals:(1) Closely spaced multiple signals caused
resolution threshold:Minimum distance between a pair of by multiple reflections in a thin material. (2) Signals
points or parallel lines when they can be distinguished as caused by continued vibration of a transducer. 7.12
two, not one, expressed in minutes of arc. Vision acuity
in such a case is the reciprocal of one half of the period ringing time: The time that the mechanical vibrations of a
expressed in minutes.V" transducer continue after the electrical pulse has
resolving power: The ability of detection systems to sepa- stopped.7•12
rate two points in time or distance. Resolving power rinse: The process of removing liquid penetrant testing
depends on the angle of vision and the distance of the
sensor from the test surface. Resolving power in vision materials from the surface of a test object by means of
systems is often measured using parallel lines. Compare washing or flooding with another liquid, usually water.
resolution.8 Also called wash.2
resonance: The condition in which the frequency of a forc- riser:A reservoir of molten metal connected to the casting
ing vibration (ultrasonic wave) is the same as the natu- to provide additional metal to the casting, required as
the result of shrinkage before and during solidification.3
ral vibration frequency of the propagation body (test
object), resulting in large amplitude responses at that robotic system: Automated system programmed to per-
frequency. 7•10 form purposeful movements in variable sequences.8
resonance method: A method using the resonance princi-
ple for determining velocity, thickness or presence of rod: Retinal receptor that responds at low levels of lumi-
laminar discontinuities.7 nance even below the threshold for cones. At these lev-
els there is no basis for perceiving differences in hue
resonant frequency: The frequency at which a body vi- and saturation. No rods are found in the fovea cen-
brates, that frequency being sympathetic to the energy tralis.8•20
causing the vibration.
roof angle: In a dual element delay line transducer, the
response or response time: The time (time-constant) angle by which the top surfaces of the delay line are
required for a leak detector or leak testing system to yield tilted horizontally to direct the beams of the two ele-
a signal output equal to 63 percent of the maximum sig- ments to intersect at a specified zone in the medium. 7
nal attained when tracer gas is applied continuously for
an indefinitely long period to the leak detector probe.1 root crack:A crack in either the weld or heat affected zone
at the root of a weld.2
root penetration: The def th to which weld metal extends
into the root of a joint.
RT: Radiographic testing.
554 I NONDESTRUCTIVE TESTING OVERVIEW
runner: ( 1) A channel through which molten metal flows scaling: (1)Forming a layer of oxidation product on metals,
from one receptacle to another. (2) The portion of the usually at high temperatures. (2) Deposition of insolu-
gate assembly that connects the downgate sprue or riser ble constituents on a metal surface, as in cooling tubes
with the casting. (3) Parts of patterns and finished cast- and water boilers.8.19
ings corresponding to the described portion of the gate
assembly.3 scanning: Movement of the transducer over the surface of
the test object in a controlled manner so as to achieve
runner box: A distribution box that divides the molten complete coverage. May be either contact or immer-
metal into several streams before it enters the mold sion method. 7
cavity.3
scarfing: Cutting surface areas of metal objects, ordinarily
runout: The discontinuity in a casting caused by the escape by using a gas torch. The operation permits surface dis-
of metal from the mold.3 continuities to be cut from ingots, billets or the edges of
plate that is to be beveled for butt welding.3
s
scattering: (1) Random reflection and refraction of radia-
salvage tests: Testing after salvage operations or testing tion caused by interaction with material it strikes or
objects that can be repaired.2 penetrates. (2) Random reflection of ultrasonic waves
by small discontinuities or surface irregularities.7
sampling probe: See detector probe.
sampling, partial: Testing of less than one hundred per- Schlieren system:An optical system used for visual display
of an ultrasonic beam passing through a transparent
cent of a production lot. See one hundred percent test medium.7•9.12
ing.8
sampling, random partial: Partial sampling that is fully scoring: (1) Marring or scratching of any formed part by
random.8 metal pickup on a punch, die or guide. (2) Reducing the
sampling, specified partial: Partial sampling in which a thickness of a part along a line to weaken it purposely at
particular frequency or sequence of sample selection is a specific location.8,19
prescribed. An example of specified partial sampling is
the testing of every fifth unit.8 scotopic vision: Dark adapted vision, using only the rods in
sand: A granular material resulting from the disintegration the retina, where differences in brightness can be de-
of rock. Foundry sands are mainly silica. Bank sands are tected but differences in hue cannot. Vision is wholly
found in sedimentary deposits and contains less than 5 scotopic when the luminance of the test surface is
percent clay. Dune sand occurs in wind blown deposits below 3 x 10-S cd-mf (2.7 x 10-6 cd.fr=). Also known as
near large bodies of water and is very high in silica con- parafoveal vision. Compare mesopic vision and pho
tent. Molding sand contains more than 5 percent clay, topic vision.8
usually between 10 and 20 percent. Silica sand is a
granular material containing at least 95 percent silica scrap: (1) Manufactured materials not suitable for sale.
and often more than 99 percent. Sand core is nearly (2) Discarded metallic material that may be reclaimed
pure silica. Miscellaneous types of sand include zircon, through melting and refining.3
olivine, calcium carbonate, lava and titanium minerals.3
saturation: (1)A condition in which high amplitude signals scuffing:A type of adhesive wear:
on a display screen do not increase with increased gain
and appear flattened.7 (2) Relative or comparative color sea level atmospheric pressure or sea level barometric
characteristic resulting from a hue's dilution with white pressure: See atmospheric pressure.
light.8
saturation level: See magnetic saturation. sealing: (1)Closing pores in anodic coatings to render them
scab: A flat volume of metal joined to a casting through a less absorbent. (2) Plugging leaks in a casting by intro-
small area. Usually set in a depression, a flat side being ducing thermosetting plastics into porous areas and
separated from the metal of the casting proper by a thin subsequently setting the plastic with heat.3
layer of sand.3
scalar: A quantity completely specified by a single num- seam: ( 1) On the surface of metal, an unwelded fold or lap
ber.4.14 that appears as a crack, usually resulting from a discon-
tinuity obtained in casting or working. (2) Mechanical
scale: Oxide formed on metal by chemical action of the sur- or welded joints.3 (3) Longitudinal surface discontinu-
face metal with oxygen from the air.2 ity on metal originating from a surface crack or blow-
hole near the surface of the ingot, that is drawn out
scale pit: Shallow surface depression in metal, caused by during rolling and follows the rolling direction. Also
scale.2 due to overfill while rolling. After forging, seams gen-
erally follow the direction of flow lines.2
search coil: A detection coil that is usually smaller than the
excitation coil.4
NONDESTRUCTIVE TESTING GLOSSARY I 555
search unit: An assembly comprising a piezoelectric ele- sensitization: Precipitation of chromium carbides in the
ment, backing material (damping), wear plate or wedge grain boundaries of a corrosion resistant alloy, resulting
(optional) and leads enclosed in a housing. Also called in intergranular corrosion that would otherwise be
transducer or probe.7 resisted. 8
second stage replica: A positive replica made from the settling test: A procedure used to determine the concen-
first cast to produce a duplicate of the original surface.a tration of particles in a magnetic particle bath. 6
secondary creep: Second stage of creep, where deforma- SH wave: See shear horizontal wave.
tion proceeds at a constant rate and less rapidly than as
in primary creep. Essentially an equilibrium condition shadow:A region in a test object that cannot be reached by
between the mechanisms of work hardening and recov- ultrasonic energy traveling in a given direction. Caused
ery.a by geometry or the presence of intervening large dis-
continuities. 7
secondary magnetic flux: magnetic flux due to induced
flow of eddy currents.4 shadow casting: Nondestructive technique of vapor
depositing a thin metal film onto a replica at an oblique
seeability: The characteristic of an indication that enables angle in order to obtain a micrograph of a test surface of
an observer to see it against the adverse conditions of an opaque specimen.f
background, outside light etc.2
shakeout:Removing castings from a sand mold.3
segregation: Nonuniform distribution of alloying ele-
ments, impurities or microphases.2•3 shallow discontinuity:A discontinuity open to the surface
of a solid object that possesses little depth in proportion
selectivity:The characteristic of a test system that is a mea- to the width of this opening. A scratch or nick may be a
sure of the extent to which an instrument is capable of shallow discontinuity in this sense.2
differentiating between the desired signal and distur-
bances of other frequencies or phases.4•13 shear: A force that tends to cause two contiguous parts of
the same body to slide in a direction parallel to their
self emulsifiable:Describes a penetrant that spontaneous- plane of contact.2
ly emulsifies into water, a property that allows it to be
rinsed off with water, with more control than if it actu- shear break: Open break in metal at the periphery of a
ally dissolved in the rinse water. Also called water wash bolt, nut, rod or member at approximately a 45 degree
able. See penetrant, water washable.2 angle to the applied stress. Occurs most often with
flanged products. Also called shear crack.8•19
self inductance:The property of an electric circuit where-
by an electromotive force is induced in that circuit by a shear crack:See shear break.
change of current in the circuit.vl"
shear horizontal wave: A shear wave in which the particle
semipermanent mold: A permanent mold in which sand vibration is parallel to the incidence surface. Abbrevi-
or plastic cores are used.3 ated SH wave. 7
send/receive transducer:A transducer consisting of two shear vertical wave: A shear wave in which the particle
piezoelectric elements mounted side by side separated vibration is perpendicular to the direction of wave
by an acoustic barrier. One element transmits, one propagation but essentially normal to the incidence sur-
receives.l'? face. Abbreviated SV wave. 7
sensing coil: A coil that detects changes in the magnetic shear wave: A type of wave in which the particle motion is
field produced by the flow of eddy currents in a test perpendicular to the direction of propagation. 7•12
specimen, induced by an excitation coil. Sensing and
excitation coils can be one and the same.4 shear wave transducer: An angle beam transducer or
straight beam transducer designed to cause mode con-
sensitivity:A measure of a sensor's ability to detect small verted shear waves to propagate at a nominal angle in a
signals. Limited by the signaltonoise ratio. 7 specified test medium. 7
sensitivity of leak detector: Response of a leak detector shell core: A shell molded sand core.3
to tracer gas leakage (typically panel meter pointer
deflection in scale divisions;leak sensitivity is measured shell molding: Forming a mold from thermosetting resin
in units of Pa,m3,s-1 or std cm3-s-1).1 bonded sand mixtures brought in contact with pre-
heated metal patterns, resulting in a firm shell with a
sensitivity of leak test: The smallest leakage rate that an cavity corresponding to the outline of a pattem.3
instrument, technique or system can detect under spec-
ified conditions (implies minimum detectable leakage shielding:A conducting or magnetic material placed so as to
rate).1 decrease susceptibility to interference and to increase
resolution+
sensitivity panel: A plated metal panel with cracks of
known depth induced into the plating. Used to evaluate shift: A casting discontinuity caused by mismatch of cope
and compare penetrant sensitivity.2 and drag or of cores and mold.3
556 I NONDESTRUCTIVE TESTING OVERVIEW
shoe: A device used to adapt a straight beam transducer for skin: A thin outside metal layer, not formed by bonding as
use in a specific type of testing, including angle beam or in cladding or electroplating, that differs in composi-
surface wave tests and tests on curved surfaces.12 See tion, structure or other characteristic from the main
also wedge. 7 mass of metal.3
shot:A short energizing cycle in a magnetic particle test. 6·16 skin depth: See depth of penetration.
skin effect: The phenomena wherein the depth of penetra-
shot peening: Cold working the surface of a metal by
metal shot impingement. Used to clean a part surface tion of electrical currents into a conductor decreases as
before inspection. 3 the frequency of the current is increased. At very high
frequencies, the current flow is restricted to an
shoulder: Cylindrical metal component surface, machined extremely thin outer layer of the conductor. See depth
to receive threading indentations but in fact not of penetration. 4.13
threaded, where the thread stops on the outside surface skip distance: In angle beam tests of plate or pipe, the dis-
of the pipe.8 tance from the sound entry point to the first reflection
point on the same surface. See Vpath. 7.12
shrink:Internal rupture occurring in castings due to con- slag: A nonmetallic product resulting from the mutual dis-
traction during cooling, usually caused by variations in solution of flux and nonmetallic impurities in smelting
solidification rates in the mold. Includes shrinkage and refining operations.3
sponge, small voids (stringers or bunches) or a finger- slag inclusions: Nonmetallic solid material entrapped in
print pattern of semifused seams. Also applied to sur- weld metal or between weld metal and base metal.2•3
face shrinkage cracks.2·6 slag lines: Elongated cavities containing slag or other for-
eign matter in fusion welds.2·3
shrink mark:A surface depression on a casting that some- slide: Part of a die generally arranged to move parallel to
times occurs next to a thick section that cools more the parting line, the inner end forming a part of the die
slowlythan adjacent sections.3 cavity wall and -involving one or more undercuts and
sometimes including a core or cores.3
shrinkage cavities: Cavities in castings caused by lack of sliver: A discontinuity consisting of a very thin elongated
sufficient molten metal as the casting cools.2•3 piece of metal attached by only one end to the parent
metal into whose surface it has been rolled. 2
shrinkage cracks:Hot tears associated with shrinkage cav- slurry:A free-flowing pumpable suspension of a fine solid
ities. 2,3 in a liquid.6
slush casting: A casting made by pouring an alloy into a
shrinkage porosity or sponge: Porous metal often with a metal mold, allowing it to remain long enough to form a
network of fine cracks formed during solidification of thin shell and then pouring out the remaining liquid.3
molten metal. At surface, may form a localized, lacy or smoothing: In image processing, use of positive coeffi-
honeycombed penetrant indication.2 cients in a linear combination of pixel values to
smoothen abrupt transitions in a digital image. Also
SI: The International System of units of measurement. An called low pass filtering. 8
international system of measurement based on seven snap flask: A hinged flask removed from the mold after the
units: meter (m), kilogram (kg), second (s), kelvin (K), mold is made.3
ampere (A), candela (cd) and mole (mol). See also Snell's law: The physical law that defines the relationship
MKSA.4.14 between the angle of incidence and the angle of refrac-
tion. 7
signal: Response containing relevant information.t+'
sniffer probe: See detector probe.
signal electrode: Transparent conducting film on the inner sniffer test: See detector probe test.
surface of a vidicon's faceplate and a thin photoconduc- SNT-TC-lA: See ASNT Recommended Practice No.
tive layer deposited on the film.8
SNTTClA.
signal processing: Acquisition, storage, analysis, alteration
and output of digital data through a computer. 8 soak time: The period of time when the emulsifier remains
in contact with the liquid penetrant on the surface of the
signal-to-noise ratio:The ratio of signal values (responses test object. Soak time ceases when the penetrant emulsi-
that contain relevant information) to baseline noise val- fier is quenched with water or completely removed by
ues (responses that contain nonrelevant information). water rinsing. Alsocalled emulsification time.2
See noise. 4.7.13
soaking:Prolonged holding at a selected temperature.3
simple magnifier: A microscope having a single converg- soldiers:Wooden blocks or sticks used to reinforce bodies of
ing lens.8
sand in the cope. They usually overhang the mold cavity.3
skim gate: A gating arrangement designed to prevent the
passage of slag and other undesirable material into the
casting.3
skimmer:A tool for removing scum, slag and dross from
the surface of molten metal.3
NONDESTRUCTIVE TESTING GLOSSARY I 557
solidification shrinkage: The decrease in volume of a spectroradiometry: Measurement of electromagnetic
metal during solidification.2·3 radiant power and spectral emittance, used particularly
to examine colors and to measure the spectral emit-
solution heat treatment:A heat treatment that causes the tance oflight sources.8
hardening constituent of an alloy to go into solid solu-
tion, followed by a quench to retain it temporarily in a spectroscope: Instrument used for spectroscopy.8
supersaturated solution state at lower temperatures.3
spectroscopy:Spectrophotometry or spectroradiometry in
solvent action: The ability of a liquid to dissolve another which the spectrum, rather than being analyzed only by
a processing unit, is presented in a visible form to the
material.2 operator for organoleptic examination.8
solvent cleaning: The process of removing excess pene-
spectrum:(1) The amplitude distribution of frequencies in
trant from the surface of a test object by hand wiping a signal.7 (2) Representation of radiant energy in adja-
with a solvent dampened cloth.2 cent bands of hues in sequence according to the
solvent developer: A developer for penetrant tests in energy's wavelengths or frequencies. A rainbow is a well
which the developing powder is applied as a suspension known example of a visible spectrum.8
or solution in a quick drying solvent.2
solvent remover: A volatile liquid that can dissolve pene- spectrum response: The amplification (gain) of a receiver
trant and that is used to remove excess surface pene- over a range of frequencies.7
trant from test objects by appropriate hand wiping
techniques. 2 specular:Pertaining to a mirror-like reflective finish, as of a
source: The location where an event takes place.5 metal. Compare lambertian.8
source location:The computed origin of acoustic emission
specular reflection: When reflected waves and incident
signals.5 waves form equal angles at the reflecting surface.8
spalling: Cracking or flaking of small particles of metal,
speed of light: The speed of all radiant energy, including
usually in thin layers, from the surface of an object.2 light, is 2.997925 x 108 m- s-1 in vacuum (approximately
spalling fatigue: See subcasefatigue. 186,000 mi· s-1). In all materials the speed is less and
spatial resolution: Width of smallest region from which varies with the material's index of refraction, which
itself varies with wavelength. 8,20
reliable data can be extracted."
specific acoustic impedance: See acoustic impedance. speed of vision:The reciprocal of the duration of the expo-
specific examination: In certification of nondestructive sure time required for something to be seen.8,20
testing personnel, a written examination that addresses spherical wave: A wave in which points of the same phase
the specifications and products pertinent to the applica- lie on surfaces of concentric sphercs.l''?
tion. Compare general examination and practical exam
ination. 8 spheroidizing: Heating and cooling to produce a
spheroidal or globular form of carbide in steel.3
specification:A set of instructions or standards invoked by
a specific customer to govern the results or perfor- split gate: A gate having the sprue axis in the die parting.3
mance of a specific set of tasks or products.8
spot check tests: Testing a number of objects from a lot to
specimen grating: In moire and grid nondestructive test- determine the lot's quality, the sample size being cho-
ing, a real grating, usually crossed lines, printed or sen arbitrarily, such as five or ten percent. This does not
embossed on the surface of a specimen. It deforms with provide accurate assurance of the lot's quality.2
the specimen as the specimen is loaded. 9
spot examination:Local examination of welds or castings.2
spectral power distribution:The radiant power per unit
wavelength as a function of wavelength. Also known as spray scrubber:Technique of pressure washing nonwater
spectral energy distribution, spectral density and spec soluble penetrant from the surface by introducing a hy-
tral distribution. 8 drophilic emulsifier or detergent into the water wash.2
spectral reflectance: The radiant flux reflected from a sprue:(1) The channel that connects the pouring basin with
material divided by the incident radiant flux.8 the runner. (2) Sometimes used to mean all gates, ris-
ers, runners and similar scrap. Also called downsprue or
spectral transmittance:The radiant flux passing through a downgate.3
medium divided by the incident radiant flux.8
spurious echo: A general term used for any indication that
spectrophotometer: Instrument used for spectrophotom cannot be associated with a discontinuity or boundary
etry. 8 at the location displayed.7
spectrophotometry: Measurement of electromagnetic squid: An acronym (superconducting quantum interfer-
radiant energy as a function of wavelength, particularly ence device). A sensitive detector of magnetic fields
in the ultraviolet, visible and infrared wavelengths.8 using a quantum effect.4
spectroradiometer: Instrument used for spectroradiom squint angle: The angle by which the ultrasonic beam axis
etry. 8 deviates from the probe axis.7
squirter:See water column.
558 I NONDESTRUCTIVE TESTING OVERVIEW
standard: (1) A physical object with known material char- straight beam: An ultrasonic wave traveling normal to the
acteristics used as a basis for comparison or calibration.
(2) A concept established by authority, custom or agree- test surface.7·12
ment to serve as a model or rule in the measurement of
quantity or the establishment of a practice or proce- strain: The alteration of the shape of a material by external
dure. 7·12 (3) Document to control and govern practices
in an industry or application, applied on a national or forces.
international basis and usually produced by consensus.
See also acceptance standard, working standard and stress: (1) In physics, the force in a material that resists
reference standard. 4.s.13
external forces such as tension and compression.
standard abnospheric conditions: Atmospheric pressure (2) Force per unit area.8
of 101.325 kPa (14.6959 lbrin.-2). Temperature of 20 °C
(293.15 K, 68 °For 527.67 °R). The density of dry air at stress corrosion cracking: Failure by cracking under
these conditions is 1.2041 kg-m-3(0.07517 Ib-fr-').'
combined action of corrosion and stress, either applied
standard barometric pressure at sea level: See atmo
spheric pressure. or residual. Cracking may be either intergranular or
transgranular, depending on the metal and corrosive
standard depth of penetration: See depth of penetration.
medium.2
standard leak: A device that permits a tracer gas to be
introduced into a leak detector or a leak testing system stress raiser: Contour or property change that causes local
at a known rate to facilitate tune up and calibration of concentration of stress.8
the leak detector or test system.1
stress relieving: Heating to a suitable temperature, hold-
standard observer response curve: See eye sensitivity
curve. ing long enough to reduce residual stresses and then "
standing wave: A wave in which the energy flux is zero at cooling slowly enough to minimize the development of
all points. Such waves result from the interaction of new residual stresses.3
similar waves traveling in opposite directions as when
reflected waves meet advancing waves. A particular stress riser: See stress raiser.
case is that of waves in a body whose thickness is an
itnestetignrga.l7.1mo.1u2ltiple of half-wavelengths, as in resonance stringer: In wrought materials, an elongated configuration
steady state: Thermal equilibrium, a condition of an object of microconstituents or foreign material aligned in the
wherein the temperatures throughout the object
remain constant. 9 direction of working. Commonly, the term is associated
with elongated oxide or sulfide inclusions in steel.2
steel: An iron alloy, usually with less than two percent car-
bon." structural integrity test (SIT):A test that demonstrates
Stefan-Boltzmann Law:Relationship governing the wave- the capability of a vessel to withstand specified internal
length independent rate of emission of radiant energy
per unit area. The law relates the total radiation inten- pressure loads.1
sity to the fourth power of absolute temperature and
emissivity of the material surface. For example, inten- subcase fatigue: Fatigue originating below the case depth.
sity (heat flow) from a copper block at 100 °C (212 °F) Compare case crushing. See also spallingfatigue.8
is 300 W-m-2 (95 BTU.fr2-h-1). (Stefan-Boltzmann
constant for photon emission = 1.52041 x 1015 pho- subcase origin fatigue: See subcasefatigue.
ton·s-1-m-2-K-2.)9
substrate: Layer of metal underlying 2a coating, regardless
stepped wedge: A device used, with appropriate pene- of whether the layer is base metal.
trameters on each step, for the inspection of parts hav-
ing great variations in thickness or complex geometries. subsurface discontinuity: Any discontinuity that does not
The stepped wedge must be made of material radio-
graphically similar to that being radiographed.'! extend through the surface of the object in which it
exists.2 See near surface discontinuity.
stereo photography: Close range photogrammetric tech-
nique involving the capture and viewing of two images subsurface fatigue: Fatigue cracking that originates below
of the same object in order to reconstruct a three the surface. Usually associated with hard surfaced or
dimensional image of the object.8
shot peened parts but may occur anytime subsurface
stresses exceed surface stresses.8
suppression: See reject.
surface wave: See Rayleigh wave.
survey meter: A portable instrument that measures dose
rate of exposure or radiation intensity+'
suspension: (1) A two-phase system comprising finely
divided magnetic particles dispersed in a liquid vehi-
cle.2 (2) Liquid bath, often a petroleum distillate, in
which solid particles are suspended.4•6 See vehicle.
SVwave: See shear vertical wave.
sweep: The uniform and repeated movement of a spot
across the screen of the cathode ray tube to form the
horizontal baseline. 7
sweep delay: A delay in time of starting the sweep after the
itnimitiea.l7.p12ulse. Also denotes the control for adjusting the
NONDESTRUCTIVE TESTING GLOSSARY I 559
sweep length: The length of time or distance represented tesla meter: A magnetometer that registers field strength
by the horizontal baseline on an A-scan.7·12 in gauss (or tesla).6
swinging field: See multidirectional magnetization. test coil: The section of a coil assembly that excites and/or
detects the magnetic field in the material under elec-
T tromagnetic test.4•13
tangential field: Magnetic field at the object's surface par- test frequency: In electromagnetic testing, the number of
allel to the surface. The tangential field runs uniformly complete cycles per unit time of the alternating current
along the material/air interface and is generally weaker
than the field in the object. Measurement can be influ- applied to the primary test coil.4•13
enced by external fields.6 test piece: A part subjected to testing.
test quality level: See level, rejection.
tape head probe: The head of a tape recorder used as an test ring:A ring specimen typically made of tool steel, con-
eddy current coil. A type of horseshoe coil.4
taining artificial subsurface discontinuities used to eval-
Tarasovetching technique: Way of visually inspecting for uate and compare the performance and sensitivity of
the presence of deleterious effects in hardened steels magnetic particles.S'"
by using specific etching solutions and methods of
inspection. a test surface:The exposed surface of a test object.2·7
thermal:Physical phenomenon of heat involving the move-
temper: (1) In heat treatment, reheating hardened steel or
hardened cast iron to some temperature below the ment of molecules. Compare infrared radiation.9
eutectoid temperature for the purpose of decreasing thermal conductivity vacuum gage: Instrument that
the hardness and increasing the toughness. The process
also is sometimes applied to normalized steel. (2) In operates on principle that as gas molecules are removed
tool steels, temper is inadvisedly used to denote the car- from a system, the amount of heat transfer by conduc-
bon content. (3) In nonferrous alloys and in some fer- tion is reduced. This relationship is used to indicate
rous alloys (steels that cannot be hardened by heat absolute pressure. 1
treatment), the hardness and strength produced by thermal diffusivity: The speed at which heat diffuses
mechanical or thermal treatment or both are character- through an object. Expressed as the rate of temperature
ized by a certain structure, mechanical properties or change with time and represented by a. Each material
reduction in area during cold working.3 has its own characteristic value for a, combining the
overall influence of thermal conductivity, density and
temper brittleness: Brittleness that results when certain specific heat. In a practical sense, thermal diffusivity
steels are held within, or are cooled slowly through, a determines how fast a material will heat up or cool
certain range of temperature below the transformation down. The rate of temperature change with time is
range. The brittleness is revealed by notched bar more rapid in a material with a high thermal diffusivity
impact tests at or below room temperature.3 (e.g., metals) and slower in a material with a lower dif-
fusivity (e.g., plastics).9
temperature:A measure of the intensity of particle motion thermal equilibrium: Condition of an object wherein
in degrees Celsius (°C) or degrees Fahrenheit (°F) or, temperatures throughout the object remain constant.9
in the absolute scale, kelvin (K) or degrees Rank- thermography:Imaging or viewing of an object or process
ine (0R), where 1 K = 1 °C = 1.8 °R = 1.8 °F. Compare through sensing of infrared radiation emitted by it. The
heat.9 temperature patterns on the material surface produce
corresponding radiation patterns. Thus, heat flow by
temperature diagram:See time temperature transforma both conduction and radiation may be observed and
tion (TTT) diagram. used to locate material discontinuities.9
three-way sort: An electromagnetic sort based on a test
temperature envelope: The temperature range over object signal response above or below two levels estab-
which a particular penetrant testing technique will lished by three or more calibration standards.vP
operate.2
threshold: See adaptive thresholding, resolution threshold
tempering: Process of heating a material, particularly hard- and threshold level.
ened steel, to below the austenite transformation tem-
perature to improve ductility.8 threshold level: The setting of an instrument that causes it
to register only those changes in response greater or
tertiary creep: Third stage of creep, marked by steady less than a specified magnitude.4•13
increase in strain to the point of fracture under constant
load.8 thresholding: Digital data processing technique that
reduces a gray level image into a binary image.8
tesla: The SI unit of measure for magnetic flux density.
Abbreviated T. 1 T = 10,000 gauss.6 throat, actual: Shortest distance from the root of a fillet
weld to its face, as opposed to theoretical throat or
weld size.8
560 I NONDESTRUCTIVETESTING OVERVIEW
throat, theoretical: The distance from the beginning of tracer: In leak testing, a gas that is sensed as it escapes from
the root of the weld perpendicular to the hypotenuse of confinement.8
the largest right triangle that can be inscribed within
the cross section of the fillet weld. Compare weld size. 8 tracer gas: A gas that can be detected by a specific leak
detector and thus disclose the presence of a leak in a
throat, weld: Distance from the root of a fillet weld to its system. Also called search gas.1
face. Compare weld size and throat, actual.8
tracer probe test: A leak test in which a tracer gas is
throttling: Reducing the net pumping speed of a pumping applied by means of a probe to an accessible test sur-
system by partially closing a valve or installing a section face on an evacuated test object so that the area cov-
of pipeline with low conductance.1 ered by the tracer gas is localized. A leak detector in the
line to the vacuum pump enables individual leaks to be
through-coil method: See coil method. located when they admit tracer gas.1
throughput:Quantity of gas, or total number of molecules
tracer standard leak: A standard leak in which the con-
at a specific temperature, passing a section of a vacuum
system per unit of time. See leakage rate.1 tained gas is a tracer gas compound.1
through-transmission:A test technique in which mag- transducer:( 1) Any device that transforms energy from one
netic or ultrasonic energy is transmitted through the
test object and received by a second transducer on the form to another. (2) In electromagnetic testing, the test
opposite side. Changes in received signal amplitude are coil.4 (3) An electroacoustical or magnetoacoustic device
evaluated as indications of variations in material conti- containing an element for converting electrical energy
nuity.7 into acoustical energy and vice versa. See search unit. 7.12
transducerrelative sensitivity:The response of the trans-
tie rod:A bar used in a casting machine to hold dies locked ducer to a given and reproducible artificial source.5
against pressure and, in general, also to serve as a way transducer, differential: A piezoelectric twin element or
along which the movable die platen slides.3 dual pole transducer, the output poles of which are iso-
lated from the case and are at a floating potential.5
TIG welding: Tungsten inert gas welding. transducer, flat response: A transducer whose frequency
time base: See sweep. response has no resonance within its specified fre-
time delay: See sweep delay. quency band (the bandwidth to -3 dB being defined),
time differential: See delta t. the ratio between the upper and lower limits of its band
time of flight: The time for an acoustic wave to travel being typically not less than 10.5
transducer, resonant: A transducer that uses the me-
between two points. For example, the time required for chanical amplification due to a resonant frequency (or
a pulse to travel from the transmitter to the receiver via several close resonant frequencies) to give high sensi-
diffraction at a discontinuity edge or along the surface tivity in a narrow band, typically ±10 percent of the
of the test object. 7 principal resonant frequency at the -3 dB points.5
time temperature transformation (TTT) diagram: A transducer, single ended: A piezoelectric single element
graph showing time required at any temperature to transducer, the output pole of which is isolated from
transform austenite to pearlite, bainite or martensite.8 the case, the other pole being at the same potential as
tip: In casual usage, the distal or objective end of a the case.5
borescope.8 transducer, wideband: A transducer that uses the mech-
toe crack:A base metal crack at the toe of a weld. 2 anical amplification due to the superposition of multi-
toggle: The linkage in a casting machine employed to mul- ple resonances to give high sensitivity in several narrow
tiply pressure mechanically in locking the dies. Also, bands within a specified wide band.5
linkage used for core locking and withdrawal in a die.3
tolerance: Permissible deviation or variation from exact transfer function: Description of changes to the waves
dimensions or standards.2 arising as they propagate through the medium or, for a
tone burst:A wave train consisting of several cycles of the transducer, the relationship between the transducer
same frequency.7 output signal and the physical parameters of the wave.5
tool mark: Shallow indentation or groove made by the
. movement of manufacturing tools over a surface. Com- transformation diagram: See time temperature transfor
pare gouge or nick. 8 mation (TTT) diagram.
toroidal field: An induced magnetic field occurring in a
ring test object when current is induced. See current transition flow: Phenomenon that occurs when the mean
induction technique. 6 free path of gas is about equal to the cross sectional
torr: Unit of absolute pressure nearly equal to 1.33332 kPa dimension of a leak or the tube through which flow is
(1.000 mm Hg).1 occurring. 1
trace: Line formed by an electron beam scanning from left transient heat flow:Heat flow occurring during the time ii
to right on a video screen to generate a picture.8 takes an object to reach thermal equilibrium or steady
state. 9
NONDESTRUCTIVE TESTING GLOSSARY I 561
transmission angle: The incident angle of a transmitted ultraviolet radiation: ( 1) Electromagnetic radiation with
ultrasonic beam. It is zero degrees when the beam is wavelengths ranging from about 4 to about 400 nm,
perpendicular (normal) to the test surface.7J0 between visible light and X-rays. Compare near ultravi
olet radiation.8 (2) The range of wavelengths used for
transmission characteristics: Test object characteristics fluorescent nondestructive testing is typically between
that influence the passage of ultrasonic energy, includ- 320 and 400 nm. Shorter wavelengths are very haz-
ing scattering, attenuation or surface conditions. 7 ardous. Compare black light.6
transmission technique: See throughtransmission. ultraviolet radiometer: A meter, usually calibrated at
transmitter: (1) The transducer that emits ultrasonic 365 nm, used in fluorescent liquid penetrant and mag-
netic particle testing to measure the output of ultravio-
energy. (2) The electrical circuits that generate the sig- let lamps."
nals emitted by the transducer.7
transverse wave: See shear wave. underbead crack: A subsurface crack in the base metal
trimming: (1)In forging or die casting, removing the part- adjacent to the weld fusion zone.2
ing line flash and gates by shearing. (2) In castings; the
removal of gates, risers and fins.3 undercut: Undesirable depression or groove left unfilled
troland: A unit of retinal illuminance equal to that pro- by weld metal, created by melting during welding and
duced by a surface whose luminance is 1 nit when the located in base material at the toe of a weld.2•8
pupil measures 1 mm2. 1 nit = 1 candela per square
meter (1 cd-m-2).8 unit die: A die block that contains several cavity inserts for
true continuous method: Test technique in which magne- making different kinds of die castings."
tizing current is applied before application of magnetic
particles and is maintained without interruption unsharpness, geometric: The fuzziness or lack of defini-
throughout the examination.vf tion in a radiographic image resulting from the source
TIT: Time temperature transformation. size, object-to-film distance and the source-to-object
tubing string: Pipe with which oil or gas has contact as it is distance.'!
brought to the earth's surface. Also called production
string. 8 upper confidence limit: A calculated value constructed
tungsten inclusions: Inclusions in welds resulting from from sample data with the intention of placing a statisti-
solidified droplets, particles or splinters of tungsten cal upper boundary on a true leakage rate.1
from welding electrodes.2
tungsten inert gas (TIG) welding: See gas tungsten arc upset: A frame used to deepen either the cope or drag in a
welding. casting mold.3
two-way sort: An electromagnetic sort based on a test
object signal response above or below a level estab- UT: Ultrasonic testing.
lished by two or more calibration standards.v':'
v
u
V-path:In angle beam tests of plate or cylindrical sections,
U shaped coil: See horseshoe coil. the path of the ultrasonic beam in the test object from
ultrasonic: Pertaining to acoustic vibration frequencies point of entry on the front surface to the back surface
and reflecting to the front surface again. See also skip
greater than about 20 kHz.7,12 distance.1
ultrasonic absorption: The damping of ultrasonic waves
vacuum: Space containing gas at a pressure below atmo-
as they pass through a medium.I'' See attenuation coef spheric pressure.1
ficient. 7
ultrasonic spectroscopy: Analysis of the frequency con- vacuum box: Device used to obtain a differential pressure
tent of an acoustic wave. Generally performed mathe- across a weld or part of a pressure boundary that cannot
matically by using a fast Fourier transform.7 be directly pressurized.1
ultrasonic spectrum: Usually, the frequency of sound
waves ranging from 20 kHz to 10 MHz, but may extend vacuum melting: Melting in a vacuum to prevent contam-
much higher in special applications." ination from air, as well as to remove gases already dis-
ultrasonic testing: Nondestructive testing using acoustic solved in the metal. The solidification may also be
energy in the ultrasonic spectrum for interrogation.7 carried out in a vacuum or at low pressure.3
ultraviolet borescope: See borescope, ultraviolet.
vacuum pressure testing: A leak testing procedure in
which the test object containing tracer gas is placed
within an evacuated enclosure and the tracer gas is
detected after entering the enclosure.1 Also called bell
jar testing.
vacuum testing: Method of testing for leaks in which the
object under test is evacuated and the tracer gas is
applied to the outside surface of the test object.
562 I NONDESTRUCTIVE TESTING OVERVIEW
vapor pressure:The pressure exerted by the vapor of a liq- visibility: The quality or state of being perceivable by the
uid when in equilibrium with the surface of the liquid. eye. In many outdoor applications, visibilityis defined in
These limiting pressures can restrict the levels of pres- terms of the distance at which an object can be just per-
surization of enclosures with these tracer gases during ceived by the eye. In indoor applications it usually is
pressure leak testing. I,2 defined in terms of the contrast or size of a standard test
object, observed under standardized viewing conditions,
variable standard leak: A device that permits a tracer gas having the same threshold as the given object.8,20
to be introduced to the leak detector at a rate adjustable
by the operator. I visible light: Radiant energy generated in the 400 to
700 nm wavelength range.6.16
vector quantity: Any physical quantity that is specified
with both magnitude and direction and that obeys the vision: Perception by eyesight. See far vision, machine
parallelogram law of addition.vl" vision, mesopic vision, near vision, peripheral vision,
photopic vision, scotopic vision and speed of vision.8
vehicle: A liquid medium for the suspension of magnetic
particles, often a light petroleum distillate or condi- vision acuity:The ability to distinguish fine details visually.
tioned water. See carrier fluid. 6.16 Quantitatively, it is the reciprocal of the minimum
angular separation in minutes of two lines of width sub-
vent: A small opening in a mold for the escape of gases.3 tending one minute of arc when the lines are just
resolvable as separate.V"
verification test: Tests intended to confirm the capability
of the type A leak test method and equipment to deter- visual acuity:See vision acuity.
mine the containment leakage rate. I visual angle: The angle subtended by an object or detail at
vertical limit: The readable level of vertical indication on uthteespoofinatrco.8f•2o?bservation. It usually is measured in min-
an A-scan.7 visual backgroundnoise: Formations on or signals from a
vertical linearity:See linearity, amplitude. test object that constitutes the background to a discon-
tinuity. The higher the level of visual background noise,
video: Pertaining to the transmission and display of images the more difficult it is to distinguish a discontinuity.8
in an electronic format that can be displayed on a visual efficiency: Reliability of a visual system. The term
screen.8 visual efficiency uses 20/20 near vision acuity as a base-
line for 100 percent visual efficiency.8
video presentation: An electronic screen presentation in visual field: The locus of objects or points in space that can
which radiofrequency signals have been rectified and be perceived when the head and eyes are kept fixed.
usually filtered. 7.12 The field may be monocular or binocular.8,20
videoscope: Jargon for video borescope. 8 visual perception: The interpretation of impressions
transmitted from the retina to the brain in terms of
vidicon tube: Television tube that uses the photoconduc information about a physical world displayed before the
tion method. Compare image orthicon. 8 eye. Visual perception involves any one or more of the
following: recognition of the presence of something
vigilance decrement: Degradation of reliability during (object, aperture or medium); identifying it; locating it
performance of visual activities over a period of time.
See also psychophysics. 8 in space; noting its relation to other things; identifying
its movement, color, brightness or form.8· 0
virtual grating: In moire and grid nondestructive testing, visual performance: The quantitative assessment of the
closely spaced walls (or planes) of light separated by performance of a visual task, taking into consideration
darkness, created by the alternating constructive and speed and accuracy.8·20
destructive interference of two intersecting beams of visual purple: Chromoprotein called rhodopsin, the pho-
coherent light.9 tosensitive pigment of rod vision. The mechanism of
converting light energy into nerve impulses is a photo-
virtual leak: Emission of vapors within a vacuum system chemical process in the retina. Chromoprotein is trans-
that result from condensible or trapped vapors. They formed by the action of radiant energy into a succession
gradually evaporate from surfaces or escape from pock- of products, finally yielding the protein called opsin
ets raising the absolute pressure in the same manner as plus the carotenoid known as retinene. 8
a real leak.I
visual task:The appearance and immediate background of
viscous flow: The flow of gas or gas mixtures through a leak those details and objects that must be seen for the per-
or duct under conditions such that the mean free path is formance of a given activity. The term visual task is a
smaller than the cross section of the leak or opening. misnomer because it refers to the visual display itself
Viscous flow may be either laminar or turbulent and is and not the task of extracting information from it.8·20
most likely to occur during leak tests at atmospheric or
higher pressures. With vacuum conditions, the flow of
tracer gases to the leak detector element is usually by
diffusion, resulting in slow response to leaks being
probed by a tracer jet.'
NONDESTRUCTIVE TESTING GLOSSARY I 563
visual testing: Method of nondestructive testing using wear, fretting: Surface degradation caused by microweld-
electromagnetic radiation at visible frequencies.8 ing and microfractures on surfaces rubbing each other.
voids: Hollow spots, depressions or cavities. See also dis Also called chafing, friction oxidation and wear oxida
continuity and dislocation. 8 tion. See also cocoa and false brinelling. 8
VT: Visual and optical testing. wedge: A device used atongdlier.1e2ctSueletraalssoonsihcoeen.7ergy into a test
object at an acute
w
weld bead: A deposit of filler metal from a single welding
wash:A coating applied to the face of a mold prior to cast- pass.2
ing.3 weld crack:A crack in weld metal. 2
water break free: Rinse water, having the ability to cover weld line: The junction of the weld metal and the base
an entire surface in an unbroken film.2 metal or the junction of base metal parts when filler
metal is not used.2
water break test: A quality control test for conditioned
weld metal: That portion of a weld that has been melted
water. Verifies that the water's surface tension has been
during welding.2
sufficiently reduced by a wetting agent to satisfactorily
cover test objects and disperse magnetic particles. May weld nugget: The weld metal in spot, seam or projection
also be used to establish surface cleanliness before welding.2
testing.6 weld size: Thickness of weld metal - in a fillet weld the
water column:A tube filled with water and attached to the distance from the root to the toe of the largest isosceles
front of a transducer to couple an ultrasonic beam to a right triangle that can be inscribed in a cross section of
the weld.8
test object. A delay line between the initial pulse and
the front surface signal. 7Also serves as a coupling weld throat: See throat.
device. See also delay line.
welder's flash: Clinical condition, specifically keratocon-
water jet: An unsupported stream of water carrying ultra- junctivitis, commonly caused by overexposure to ultra-
violet radiation of welding arc.8
sonic signals between the transducer and the test object
surface. Also called a squirter.7 wet developer: A developer in which the developing pow-
water line: A tube or other passage through which water is udseurailslyawppaltieerdorassoalvseunstp.2ension or solution in a liquid,
circulated to cool a casting die.3 wet method: A testing technique in which magnetic parti-
water path: In immersion testing or with a water column,
cles are applied as a suspension in a liquid vehicle.6·16
tfhroendt issutarnfacceef. r7·o12m the transducer face to the test object's
wet slurry technique: A magnetic particle test in which
the particles are suspended in high viscosity vehicle.v-"
water tolerance: The amount of water that a penetrant or·
wetting action: The ability of a liquid to spontaneously
emulsifier can absorb before its effectiveness is
spread over and adhere to solid surfaces.2
impaired.2
wave interference: The production of a series of maxima wetting agent: A substance that increases wetting action
and minima of sound pressure as a consequence of the by reducing the surface tension of a liquid, thereby
superposition of waves having different phases.7.12 reducing the formation of air bubbles.2
wave train: A series of waves or groups of waves passing wheel transducer: A device that couples ultrasonic
along the same course at regular intervals.7 energy to a test object through the rolling contact area
of a wheel containing a liquid and one or more. trans-
wavefront:In a wave disturbance, the locus of points hav- ducers. 7.12
ing the same phase.7.12 white light: Light combining all frequencies in the visible
wavteiloennfgotrha:Twhaeveditsotagnoctehrnoeuegdhedaicnotmheplpertoepcaygcalteio.7n,10direc- spectrum.8
weak sand:Refers to sand that will not hold together when Wien's Displacement Law: For practical infrared imag-
ing, Wien 's Displacement Law gives the wavelength of
used to make a mold.3
wear: See erosion; rat's tooth principle; wear, adhesive; and maximum emittance.9
wear,fretting. wobble: In electromagnetic testing, an effect that produces
variations in an output signal of a test system and arises
wear face: A protective material on the face of a transducer
to prevent wear of the piezoelectric element.U'' from variations in coil spacing due to lateral motion of
wear oxidation:See wear, fretting. the test object in passing through an encircling coil.4•13
wear, adhesive: Degradation of a surface because of work hardening: Increase in hardness accompanying
microwelding and consequent fracture due to the slid- plastic deformation of a metal. Usually caused in a
ing of one surface against another. Types include fret- metal by repeated bending or flexing. Compare creep
ting, galling and scuffing.8 and recovery. 8
564 I NONDESTRUCTIVE TESTING OVERVIEW
working standard:Work piece or energy source calibrated y
and used in place of expensive reference standards. In
the calibrating of photometers, the standard would be a yoke: A U shaped magnet that induces a field in the area of
light source.8 the test object that lies between its poles (magnetic par-
ticle or flux leakage testing). Yokes may be permanent
worm holes: Elongated or tubular cavities due to magnets, alternating current electromagnets or direct
entrapped gas. Also called pipes. 2 current electromagnets.v-P
wrap around: The display of misleading ultrasonic reflec- z
tions from a previously transmitted pulse due to the use
of excessive pulse repetition frequency.21 See ghost. 7 zircon sand: A highly absorptive material used as a block-
ing or masking medium for drilled holes, slots and
x highly irregular geometries to reduce scattering during
radiography. 3
X-ray:Penetrating electromagnetic radiation emitted when
the inner orbital electrons of an atom are excited and
release energy. Radiation is nonisotopic in origin and is
generated by bombarding a metallic target with high
speed electrons.'!
NONDESTRUCTIVE TESTING GLOSSARY I 565
REFERENCES
1. Nondestructive Testing Handbook, second edition: 14. IEEE Standard Dictionary of Electrical and Electronic
Vol. 1, Leak Testing. Columbus, OH: American Soci- Terms. New York, NY: Institute of Electrical and Elec-
ety for Nondestructive Testing (1982). tronics Engineers (distributed by Wiley-Interscience, a
divisionofJohn Wiley and Sons) (1984).
2. Nondestructive Testing Handbook, second edition:
Vol. 2, Liquid Penetrant Tests. Columbus, OH: Amer- 15. Glossary of Terms Used in Nondestructive Testing,
ican Society for Nondestructive Testing (1982). Part 2. London, United Kingdom: British Standards
Institute (November 1984).
3. Nondestructive Testing Handbook, second edition:
Vol. 3, Radiography and Radiation Testing. Colum- 16. E 269-89, Standard Definitions of Terms Relating to
bus, OH: American Society for Nondestructive Test- Magnetic Particle Examination. Philadelphia, PA:
ing (1985). American Society for Testing and Materials (1989).
4. Nondestructive Testing Handbook, second edition: 17. API RP5A5, Recommended Practice for Field Inspec
Vol. 4, Electromagnetic Testing. Columbus, OH: tion of New Casing, Tubing and Plain End Drill Pipe,
American Society for Nondestructive Testing (1986). third edition. Washington, DC: American Petroleum
Institute (1987).
5. Nondestructive Testing Handbook, second edition:
Vol. 5, Acoustic Emission Testing. Columbus, OH: 18. "Ultrasonic Flaw Detection." The Glossary of Terms
American Society for Nondestructive Testing (1987). Used in Nondestructive Testing. British Standard
3683, Part 4. London, England: British Standards
6. Nondestructive Testing Handbook, second edition: Institute (1985).
Vol. 6, Magnetic Particle Testing. Columbus, OH:
American Society for Nondestructive Testing (1989). 19. EPRI Leaming Modules. Charlotte, NC: Electric
Power Research Institute (various years).
7. Nondestructive Testing Handbook, second edition:
Vol. 7, Ultrasonic Testing. Columbus, OH: American 20. IES Lighting Handbook: Reference Volume. New
Society for Nondestructive Testing (1991). York, NY: Illuminating Engineering Society of North
America (1984).
8. Nondestructive Testing Handbook, second edition:
Vol. 8, Visual and Optical Testing. Columbus, OH: 21. MIL-STD-371, Glossary of Terms and Definitions for
American Society for Nondestructive Testing (1993). Ultrasonic Testing Procedures. Washington, DC
(Department of Defense): United States Army
9. Nondestructive Testing Handbook, second edition: (October 1987).
Vol. 9, Special Nondestructive Testing Methods.
Columbus, OH: American Society for Nondestruc- 22. 1992 Annual Book of ASTM Standards. Section 3,
tive Testing (1995). Metals Test Methods and Analytical Procedures:
Vol. 03.03, Nondestructive Testing. Philadelphia, PA:
10. Weismantel, E. "Glossary of Terms Frequently Used American Society for Testing and Materials (1992).
in Nondestructive Testing." Materials Evaluation.
Vol. 33, No. 4. Columbus, OH: American Society for 23. E 1316, Standard Terminology for Nondestructive
Nondestructive Testing (1975). Examinations. Philadelphia, PA: The American Soci-
ety for Testing and Materials (1993).
11. NDT Terminology. Wilmington, DE: E.I. du Pont de
Nemours & Company, Photo Products Department 24. E 500-85, Standard Definitions of Terms Relating to
(n.d.). Ultrasonic Testing. Philadelphia, PA: American Soci-
ety for Testing and Materials (1985).
12. Nondestructive Testing Methods. T033B-l-l
(NAVAIR Ol-lA-16) TM43-0103. Washington, DC: 25. Mish, Frederick C., ed. Webster's Ninth New Colle
Department of Defense United States Air Force giate Dictionary. Springfield, MA: Merriam-Webster
(June 1984): p 1.25. (1984).
13. E 268-81, Definitions Approved for Use by Agencies 26. "Nondestructive Inspection and Quality Control."
of the Department of Defenseas Part of Federal Test Metals Handbook. Vol. 11. Metals Park, OH: Ameri-
Method Standard No. 151b and for Listing in the can Society for Metals (1976).
DoD Index of Specifications and Standards. Philadel-
phia, PA: American Society for Testing and Materials 27. ANSI/ANS-58.6. New York, NY: American National
(1981). Standards Institute (1981).
INDEX I 567
INDEX
A Aluminum
aircraft rotor wheels, immersion ultrasonic testing 414-418
alloys, eddy current testing . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Aboveground storage tanks, leak testing . . . . . . . . . . . . . . . . . . 65-69 alloys, ultrasonic testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411
Absolute eddy current transducers 203-204 bolt holes, eddy current testing 229, 231
Absolute pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 radiography 145, 146, 150, 153, 169
Absorption, of radiation 95-98, 144-146 thermography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 495-496
Accessibility limitations, on methods . . . . . . . . . . . . . . . . . . . . . . . . 13 tube walls, remote field eddy current testing of . . . . . . . . . . . . . . . . 211
Accident prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 ultrasonic beam attenuation by . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392
Accumulation method, of helium leak testing . . . . . . . . . . . . . . . . 60 ultrasonic testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 362, 411
Accuracy specification 12-14 American Conference of Governmental Industrial Hygienists
ACGIH. See American Conference of Governmental Industrial Hygienists (ACGIH) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 437
Acid pickling cracks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264-265 visual safety recommendations . . . . . . . . . . . . 439
Acoustically active/passive leaks 61 American National Standards Institute (ANSI) 299
Acoustic emission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298 ANSIIASNT CP1891991 80
felicity effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304, 316-317 ANSI Types 1 and 2 radiographic exposure devices 120-122
Kaiser effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302-303, 304 ANSI Zl36.l-1993 436
sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62-64, 301 American Petroleum Institute (API) 299
Acoustic emission testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297-344 API 575 66
advantages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299-300 API 620 66
applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300 API 650 66
bucket truck/lift inspection . . . . . . . . . . . . . . . . . . . . . . . 302, 305-309 API 651 66
fiber-reinforced plastic inspection 310-317 API 652 66
gas trailer tubing 318-321 API 653 66
resistance spot welds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323-330 American Society for Testing and Materials (ASTM) 299
undersea electronic repeaters 331-336 acoustic emission testing standards 317
computer application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302 ASTM D 4788 492
data interpretation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303-304 ASTM E 380 18
equipment for 301-302 ASTM E 427 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
frequency selection for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301-302 ASTM E 1476 503
sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303 ASTM E 799 blower doors 490
standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299 ASTM E 747 penetrameter 168
Acoustic leak testing 61-64, 300 ASTM F 914 307
multiple acoustic emission sensors . . . . . . . . . . . . . . . . . . . . . . . . 62-64 ASTM plaque penetrameter 166-167, 169
ultrasonic detection 61-62 American Society of Mechanical Engineers (ASME) 299
Acoustic nondestructive testing methods 16, 505-506 ASME Boiler and Pressure Vessel Code . . . . . . . . . . . . . . . . . . . . . 441
See also Acoustic emission testing; Sonic-ultrasonic; Ultrasonic testing American Society for Nondestructive Testing (ASNT) . . . . 2, 80, 299
Acoustoultrasonic testing 476, 506 ANSIIASNT CP1891991 80, 299
Acquired color vision deficiencies . . . . . . . . . . . . . . . . . . . . . . . . . 433 ASNT Recommended Practice No. SNTTClA 40-41, 80, 299
Action spectra 437 Ammonia sensitive paint leak testing . . . . . . . . . . . . . . . . . . . . . . . 67
Active infrared thermography . . . . . . . . . . . . . . . . . . . . . . . . 482, 484 Amplitude gating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385
Additional leakage technique . . . . . . . . . . . . . . . . . . . . . . . . . . . 51-52 Angle beam contact ultrasonic testing . . . . . . . . . . 353, 354, 355, 357
Aerial surveys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 492 for weld testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397-399, 404-406
Air coupled ultrasonic transducers 371-372 Angulated borescopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 452
Aircraft Anisotropic materials, ultrasonic wave propagation in .... 349, 350
bolt hole eddy current testing 231 Annular eddy current transducers . . . . . . . . . . . . . . . . . . . . . . . . . 204
propeller blades, borescope inspection . . . . . . . . . . . . . . . . . . . . . . 452 Anode, X-ray tubes 101, 103
rotor wheels, immersion ultrasonic testing of . . . . . . . . . . . . . 414-418 Anode grounded circuit, X-ray generators . . . . . . . . . . . . . . . . 104
tires, shearographic testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500 Anomaly location
Alloy identification 474, 475, 503, 504 thermography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 478
Aloha Airlines, fatigue crack incident involving . . . . . . . . . . . . . . . 3 X-ray computed tomography . . . . . . . . . . . . . . . . . . . . . . 195, 196
Alpha particles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 See also Discontinuity detection
Alternating current . . . . . . . . . . . . . 281 ANSI. See American National Standards Institute (ANSI)
Alternating current demagnetization . . . . . . . . . . . . . . . . . . . . . . 286 Aperture . .. 446
568 I INDEX
Appearance specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Boot attachment, for immersion ultrasonic testing 410
Archival storage, of radiographs . . . . . . . . 171 Borescopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 449-452
Array eddy current transducers . . . . . . . . . . . . . . . . . . . . . . 203 applications . . ........... 452-453
A-scan presentation, ultrasonic testing .. 356-358, 380, 381, 392, 395 construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 454-455
ASNT. See American Society for Nondestructive Testing (ASNT) diopter adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . 441
Astigmatism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429 optical systems for . . . . . . . . . . 453-454
ASTM. See American Society for Testing and Materials (ASTM) photography with .......... . . . . . . 455-456
Atmospheric pressure . . . . 54, 55 video application . . . . . . . . . . . . . . . . . . . . . . ... 459-461,466
Atmospheric pressure vessels, acoustic emission testing ... 311, 313 Bouwers/Schmidt lenses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182
Atomic number, dependence of photon absorption on . . . . . . 97-98 Bragg angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Attenuation coefficients, radiation absorption . . . . . . . . . . . 95, 98 various crystals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Automated bolt hole inspection . . . . . . . . . . . . . . . . . . . . . . . . 231 Brake cylinders (automotive), eddy current testing 234-235
Automatic bar inspection systems . . . . . . . . . . . . . . . . . . 218-222 Brazed joints. See Joints
Automobiles and components . . ....................... 6 Bridge surfaces, thermography . . . . . . . . . . . . . . . . . . 492
borescope application . . . . . . . . 452 Brightness 21, 441
eddy current testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200, 232-238 Brittle coating method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 507
thermography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 492-493 B-scan presentation, ultrasonic testing . . 356, 358-359, 380, 381, 395
Autonomous submarines . . . . . . . . . . . . . . . . . . . . . . . . . . . 465 Bubble leak testing . . . ............. . ... 40, 57-58
Autoscan techniques, for bolt hole inspection 228 bubble equivalents . . . . . . . . . . . . . . . . . . . . . . . . 41
Aviation industry, borescope application . . . . . . . . . . 452 liquid film technique . . . . . . . . . . . . . . . . . . . . . . . . . . . 57-58
See also Aircraft liquids for . . . . . . . . . . . . . . . . 57
Axle shafts (automotive), eddy current testing 232-234 sensitivity 31-32
vacuum box technique . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58, 66-67
B Bubblers, for immersion ultrasonic testing . . . . . . . . . . . . . 408-409
Bucket truck/lift inspection, using acoustic emission 302, 305-309
Buffer rods . . . . . . . . . . . . . . . . . . 401
Back lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 469 Buildings, thermography 490-491
Backscatter/absorption gas imaging (BAGI) leak testing . . . . . 39-40 Bunsen-Roscoe reciprocity law . . . . . . . . . . . . . . . . . . . . . . . 140-141
Backscattered radiation . . . . . . . . . . . . . . . . . . 146, 147 c
Back surface reflections . . . . . . . . . . . . . . . . . . . 368, 385, 410
Ball bearings, magnetic flux leakage testing . . . . . . . . . 245
Bandpass optical filters .............. 470
Bar inspection systems 218-222 Cadmium zinc sulfate . 174, 176
Barium clay . . . . . . . . . . . . . . . . . . . . 148 Calcium tungstate . 174
Barium platinocyanide . . . . . . . . . . . . . . . . . . . . . . . 174 Calibrated borescopes . . . . 452
Barkhausen effect . . . . . . . . 298, 504-505 Calibrated physical leaks ..... 49
Barkhausen noise analysis 505 Californium-252 . . 98
Bar magnets 267, 271 Cameras . 446
Beam focusing, X-ray tubes 100-101 See also Television systems
Bell jar method, of helium leak testing . . . . . . . . . . . . . . . . . . . . 60 Camshaft heat treat inspection 237-238
Berry resistance strain gage . . . ............... 506 Cannon tubes, magnetic flux leakage testing . . . . . . . . . . . . 244
Beta particles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 Cars. See Automobiles and components
Beta ray thickness gages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Case depth, of automotive parts, by eddy current
Betatrons . . . 106, 107-108 testing . . . . . . . . . 232-234, 236-237
Billet inspection system . . . . . . . . . . . . . . . . . . 222-223 Castings
Billets discontinuities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263
eddy current testing of steel. ....... 222-227 improving product design through nondestructive testing . . . . . . . . . . 5
magnetic particle testing of steel. . . . . . . . . . . . . . . . . . . . . . . . . . . . 259 internal evaluation by X-ray computed tomography . . . . . . . . ... 191
Blackbody radiation . 481-482 Cathode, X-ray tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Black light radiometers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 437 Cathode grounded circuit, X-ray generators . . . . . . . . . . . . . . . . 104
Blind spot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 430 Cathode ray tubes . . . . ................ . . 462-463
Blooms........................ . 259 Ceiling fixtures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 440
Blowholes . 260 Center grounded circuit, X-ray generators . . . . . . . . . . . . . . . . . 104
Blue hazard . 439 Ceramic capacitor acoustic emission crack detector . . . . . . 332-334
Boilers, failure . ...... 4 Ceramic ultrasonic transducers . . . . . . . . . . . . . . . . . . . . . . . . . . . 372
Boiler tubes, visual testing . . . . . . . . . . . . . . 453, 461 Cesium-137 115, 118-119, 145
Bolt hole inspection (eddy current) 228-231 Cesium iodide .......... . . 174, 176-177
Bolt hole probes . .. 230, 231 Channel electron multipliers . . . . . . . . . . . . . . 177
Bonded materials/structures, thermography 493-495 Characteristic curves, radiographic films 161-163
See also Composites Charge coupled devices
Bonding . . . . . . . . . . . .............. 44-45 radioscopy application . 179, 180
Bond testing ......... 364, 369 visual testing application . 459, 466, 471
composites, using immersion ultrasonic testing . . . . . . . . . . . . . . 423 Charge injected devices 471
INDEX I 569
Chemical composition/analysis . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 17 Countered shoes .. 400
Chemical industry, borescope application . . . . . . . . . . . . . . . . . . 453 Coupling media, for ultrasonic pulse echo testing . . . . . . . 400-403
Chief inspector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Crack detection . . . . ............................... 2
Circular magnetic fields 270 acoustic emission testing . . . . . . . . . . . . . . . . . . . . . . . . . 298, 332-334
Circumferential eddy current transducers . . . . 204 in automotive parts, by eddy current testing . . . . . . . 232, 233, 234-236
Circumferential magnetization . . . . . . . . . . . . . . 273-274 in bolt holes, by eddy current testing . . . . . . . . . . . . . 228, 229-230, 231
Cleaning, for liquid penetrant process . . . . . . . . . . . . . . . . . . . 86-87 leak testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Cleanliness, importance in visual testing . . . . . . . . . . . . . . 440 liquid penetrant testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77, 78
Cobalt-60 114-116, 117, 145 magnetic flux leakage testing . . . . . . . . . . . . . . . 242, 245-246, 250-253
Coercive force . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278, 288-289 point triangulation profilometry 501-502
Coherent photon scattering . . . 95, 96, 97 potential drop method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 503
Coils, for magnetic flux leakage testing . . . . . . . . . 246-247 radioscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186
Cold headed pinion gear eddy current testing 235-236 ultrasonic testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 347
Cold shuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263 various methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 17
Collimators, radiographic use . . . . . . . . . . . . . . . . . 122, 123 visual testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 452
Color chip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 459 See also Leaks
Color temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 434 Cracks . 260-266
Color vision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 432-434 Crater cracks .............. 263
Color vision deficiencies (color blindness) : 432-433 Cross section, for neutron absorption . . . . . . . . . . . . . 98
Comparators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 444 Cruise missile engine, internal evaluation by X-ray
Complex structure evaluation, by X-ray computed computed tomography 191, 192
tomography . . . . . . . 188, 190-192 Crystals, Bragg angle . . . . . . . . . . . . . . . . . . . . . . 94
Composites C-scan presentation, in ultrasonic testing .... 356, 359, 380-381, 395
acoustic emission testing . . . . . . . . . . . . . . . . . . . . 298, 300 CT. See X-ray computed tomography
acoustoultrasonic testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 506 Cup core eddy current probes . . . . . . . . . . . . . . . . . . . . . . 204
anisotropy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 349 Cupping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261
discontinuities . . . . . . . . . . . . . . . . . . . . . . . . . 419, 420-423 Curie point . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284
immersion ultrasonic testing . . . . . . . . . . . . . . . . . . . . . . . . . . . 419-423 Curie point heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284-285
tap testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 505 Customer satisfaction, ensuring through nondestructive testing . . 5
thermography . . . . . . . . . . . . . . . . . . . . . . . . . . . 486-489 Cycles, AC . . . . . . . . . 281
ultrasonic beam attenuation by . . . . . . . . . . . . . . . . . . . . 392-393 Cyclotrons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106-107, 108
ultrasonic pulse echo testing . . . . . . . . . 383-384, 386-388, 393-394, 395
Composite vessels, acoustic emission testing . . . . . . . 310-317 D
Composition. See Material composition
Compressed gas cylinders . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Compressibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Dead zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 384
Compton scattering . . . . . . . . . . . . . . . . . . . . . 95, 96-97 Dees 107
Computed tomography. See X-ray computed tomography Defects. See Discontinuities
Computers Definition, radiographic images 165
acoustic emission testing application . . . . . . . . . . . . . . . . 302 Deformation measurement . 497-498
component reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 See also Plastic deformation
Concealed cut (composite discontinuity) 421 Deja vu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 428
Conduction heat transfer . . . . . . . . . . . . . . . . . . . . . . 478-479 Delaminations . . . . . . . . . . ............ 419, 420, 487
Conductivity units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Delay lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . 354, 382, 401
Cone beam computed tomography . . . . . . . . . . 190 Demagnetization . . . . . . . . . . . . . . . . . . . . . . . . 258, 269, 282, 284-287
Cones (eye) . . . . . . . . . . . . . . . . . . . . 429 Densitometers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Contact pulse echo ultrasonic testing. See Ultrasonic pulse echo testing Depth of field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 446
Contact thickness gaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369 Depth of penetration, eddy currents . . . . . . . . . . . . 202, 204-205, 224
Continuous image averaging . . . . . . . . . . . . . . . . . . . . . . . 185 Derived SI units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Continuous test method, of magnetic particle testing . . . . . . . . . 292 Design engineer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Continuous X-radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 Detector probe technique, leak testing . . . . . . . . . . . . . . . . . 34-35
Contrast, radiographic images . . . . . . . . . . . . . 142, 148-149, 164-165 Developers, for penetrant testing . . . . . . . . . . . . . . . . . . . . . 77, 82-83
Contrast sensitivity, in X-ray computed tomography . . . . . . 193, 195 Diamagnetic materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268
Contrast stretching radioscopic image enhancement . . . . . . . . . 187 Diaphragms, radiographic . . . . . . . . . . . . . . . . . . . . . . . . . . . 148, 150
Control, role of nondestructive testing in quality. . . . . . . . . . . . . . . 5 Die forgings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411
Convection heat transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 478 Diesel engine pistons, eddy current testing . . . . . . . . . . . . . . . . . 235
Conventional holography . . . . . . ................. 498 Differential eddy current transducers 203-204
Cooling cracks . . . . . . . . . . . . . 261-262 Differential pressure . . . . ....................... 20
Cornea. .......................... 429 Differentiation, in vision . . . . . . . . . . . . . . . . . . . . . . 428
Corner cracking .. 264 Digital image enhancement matrix . . . . . . . . . . . . . . . 447-448
Corrosion . 266 Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 17
eddy current testing 200-201 Direct coupled zone ............ 206
Cosmic rays 92 Direct current . . . ......... 281-283
570 I INDEX
Direct current demagnetization . . . . . . . . . . . . . . . . . . . . . . . . . . . 286 Edge radioscopic image enhancement 185-187
Direct vision borescopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455 Elastic behavior . . . . . . . . . . . . . . . . . . . . . . . . 477
Discontinuities 259-266, 475 Elastic waves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350
acoustic emission signatures . . . . . . . . . . . . . . . ... 316 laser-generated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 370
composites 419, 420-423 Electrically induced magnetism . . . . . . . . . . . . . . . . . . . . . . . 273-275
grain size 413-414 Electrical power supply hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
subsurface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271 Electric power transmission systems, thermography of 491
thermal diffusivity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 479-480 Electric resistance strain gages . . . . . . . . . . . . . . . . . . . . . . . . . . . 507
Discontinuity detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Electromagnetic acoustic transducers (EMATs) . . . . . . . . . 373-374
acoustic emission testing 298, 314-315, 318-321 Electromagnetic demagnetization . . . . . . . . . . . . . . . . . . . . . . . . . 285
composites, by thermography . . . . . . . . . . . . . . . . . . . . . . . . . . 486-489 Electromagnetic-electronic methods 16
composite tubing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 420-422 Electromagnetic induction testing . . . . . . . . . . . . . . . . . . . . . . . . . 200
eddy current testing . . . . . . . . . . . . . . . . . . 200, 202, 218-219, 220, 222 geometric limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
failure and . . . . . . . . . . . . . . . . . . . . . . . . . . . .......... 4 special methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 503-505
infrared thermography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 485 units for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
liquid penetrant testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77-78 See also Eddy current testing; Magnetic flux leakage testing
magnetic flux leakage testing . . . . . . . . . . . . . . . 242, 245-246, 250-253 Electromagnetic radiation . . . . . . . . . . . . . . . . . . . . . . . . . . 92-94, 480
magnetic particle testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258-266 absorption 95-98, 144-146
potential drop method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 503 scattering 95, 96-98, 146-150
shearography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500 Electromagnetic radiation shielding . . . . . . . . . . . . . . . . . . . 112, 123
ultrasonic testing . . . . . . . . . . . . 347, 352, 354, 365, 369 Electromagnetic sorting techniques 212-217
immersion technique 410-414 Electromagnetic spectrum . . . . . . . . . . . . . . . . . . . . . . . . . 92, 434, 480
straight beam pulse echo technique . . . . . . . . . . . . 384-388, 394-395 Electron beam distribution, from X-ray tubes . . . . . . . . . . . . . . . 102
various methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 17 Electron capture detector probe leak testing . . . . . . . . . . . . . . . . 68
visual testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 452, 463-464 Electronic holography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 498
See also Crack detection Electrostatic ultrasonic transducers . . . . . . . . . . . . . . . . . . . . . . . 371
Dosimeters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112, 127 Emissivity 481-482, 483-485
Double bottom storage tanks, leak testing . . . . . . . . . . . . . . . . 65-68 selected materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 485
Dry powder magnetic particles 289, 290-291 Emulsifiers, in liquid penetrant testing . . . . . . . . . . . . . . . . . . . . . 82
Dry powder penetrant developers . . . . . . . . . . . . . . . 82 Emulsions, radiographic ftlms ............. 157
Dual mode penetrants . . . . . ......... 81 EN 473 80
Dunegan corollary, to the Kaiser effect . . . 304 Encircling eddy current transducers . . . . . . . . . . . . . . . . . . . . . . . 204
Dynamic leak testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36, 37 high temperature application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224
Dynamic method, of helium leak testing . . . . . . 60 English units, conversions to SI units . . . . . . . . . . . . . . . . . . . . . . . 19
Dynamic response . . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 17 Enlargement, radiographic images . . . . . . . . . . . . . . . . 134, 138
Envelopes, for X-ray tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
E Environmental contamination, leak testing to prevent . . . . . . . . . 30
Environmental Protection Agency . . . . . . . . . . . . . . . . . . . . . . . . 7
Etching cracks . . . . . ........... . 264-265
Earth's magnetic field 267, 268-269 Evacuated systems. See Vacuum systems
and demagnetization process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287 Explosion hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
E-core eddy current probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 Exposure, radiographic images . . . . . . 133-134, 137, 141-142, 159-161
Eddy current impedance plane . . . . . . . . . . . . . . . 212-213 Expulsion, in spot welding . . . . . . . . . . . . . . . . . . . . . . . . . . . 324, 327
edge and liftoff effects on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213-217 Eye . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 428-430, 432-434
Eddy current probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200, 204 light-dark effects . . . ....................... 435
Eddy currents . . . . . . 200-201 Eyeglasses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 430
penetration depth 202, 204-205, 224 Eye protection filters . ................. 439
Eddy current testing
applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200, 202-203 F
automotive industry . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200, 232-238
bolt hole inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228-231
steel industry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218-227 Fabrication discontinuities . . . . . . . . . . . . . . . . . . . . . . . . 259, 263-265
detector arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201 Failure 4
limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13, 202 analysis by X-raycomputed tomography 195-196
multifrequency testing . . . . . . . . . . . . . . . . . . . . . 239-241 rising costs of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
optimal frequencies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201-202 Farsightedness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429
remote field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206-211 Far vision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429
signalanalysis . . . . . . . . . . . . . . . . . . . . . . . . . 201 Far vision examinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 430
Eddy current transducers . . . . . . . . . . . . . . . . . . . . 200, 203-204 Fastener holes, eddy current testing . . 228-231
high temperature application . . . . . . . . . . . . 224-225 Fatigue cracking . . . . . . . . . . . . . . . . . . . 266
Edge effect ultrasonic testing . . . . . . . . . . 347
eddy current testing 213-217 See also Crack detection
immersion ultrasonic testing . . . . 412 Fatigue strength . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266
INDEX I 571
Feature extraction 468 Flying rigs . . . . 466
Federal Aviation Administration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Focused ultrasonic transducers . 390
Federal Regulations Code: Titles 10 and 49 (radioisotope Focusing, video borescopes 460
handling) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 Focusing cups, X-ray tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
Feed-through coil eddy current transducers . . . . . . . . . . . . . . . . 204 Foil resistance strain gages 507, 508
Felicity effect 304 Forging blank testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
in fiber-reinforced plastics . . . . . . . . . . . . . . . . . . . . . . . . 316-317 Forging bursts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262
Ferrite cores turbine rotor wheels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 416
eddy current testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215, 216 Forging discontinuities 262
for magnetic flux leakage testing coils 247 Forging laps 262
Ferromagnetic materials 268 Forked coil eddy current transducers 204
Barkhausen noise analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 505 Forster microprobes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248, 249
discontinuities of 259-266 Forward oblique borescopes . . . . . . . . . . . . . . . . . . . . . . . . . 455
eddy current testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213, 215, 217 Fracture point . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 477
high temperatures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223-224 Free convection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 478
production of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259 Free machining steel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278-280 Front lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 468-469
See also Magnetic particle testing; Steel Full skip (V) test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398, 405
Fiberglass laminates, thermography . . . . . . . . . . . . . . . . . . . . . . . 489 Full-wave direct current 281-283
Fiber image guides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 449-450 Future usefulness, of test objects ........................... 2
Fiber light guides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450
Fiber optics G
borescopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 449-450
radioscopy application . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182-183
Fiber reinforced composites. See Composites Gage pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Fiber reinforced plastic vessels, acoustic emission Galvanized steel, spot weld acoustic emission monitoring . . 328-329
testing 310-317 Gamma radiography . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
Field of view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 428-429 See also Radiographic isotope sources; Radiography
borescopes 451, 454 exposure
Fill factor, eddy current testing . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 exposure charts . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
Film badges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112, 127 exposure factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
Film contrast, in radiography . . . . . . . . . . . . . . . . . . . . 164-165 gamma ray equivalency . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145-146
Film radiography. See Radiographic films; Radiography isotopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114-119
Film speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 447 source handling equipment 120-127
Film thickness Gamma rays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92-93
diesel engine piston eddy current testing . . . . . . . . . . . . . . . . . . . . . 235 absorption . . . . . . . . . .............. . . 95-98, 145-146
eddy current testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232 scattering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Filters sources. See Radiographic isotope sources
eye protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 439 Gas cooled borescopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 452
optical 470 Gas trailer tubing, acoustic emission testing . . . . . . . . . . . . . 318-321
radiographic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148-150 Gated system display, in ultrasonic testing . . . . . . . . . . . . . . 356, 359
Fissures. See Crack detection Gears
Fixed grid testing . . . . . . . 497 automotive pinion gear eddy current testing . . . . . . . . . . . . . . . 235-236
Flakes . 262 eddy current testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
Flammable liquids/vapors . . . . . . . . . . . . . . . . . . . . . . . . . 44 fatigue cracking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
Flash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262 Geiger-Miiller meter . . . . . . . . . . . . . . . . 113
Flash lighting 469-470 Gelatin ultrasonic testing couplants . . . . . . . . . . . . . . . . . . . . . . . 402
Flash line tears . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262, 263 General manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Flaws. See Discontinuities Geometrical optics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 426-427
Flexible membranes, for coupling in contact ultrasonic Geometric limitations, on methods . . . . . . . . . . . . . . . . . . . . . . . . . 13
testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 400-401 Geometric unsharpness, of radiographic images 134, 136-138
Flexible resin (composite discontinuity) 421, 422 Geometry acquisition, by X-ray computed tomography 195
Fluorescence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 435 German DIN penetrameter 168
Fluorescence detection 427 Glare . . . . . . . . . . . . . 440
Fluorescent magnetic particles 289, 291 Glossary of nondestructive testing terms 516-564
Fluorescent materials . . . . . . . . . . . . . . . . . . . . . . . . . . . 435 Glycerine, as ultrasonic testing couplant . . . . . . . . . . . . . . . . . . . 402
Fluorescent penetrants . . . . . . . . . . . . . . . ...... 76, 81 Graetz circuit, X-ray generators . . . . . . . . . . . . . . . . . . . . . . . 104, 105
Fluorescent screens . . . . . ·. . . . . . . . . . . . . 154-156, 165, 166 Graininess, radiographic films . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
radioscopic use . . . . . . . . . . . . . . . . . . . . . 174 Grain size discontinuities . . . . . . . . . . 413-414
Fluoroscopy . 174 Graphite-epoxy composites, thermography . . . . . . . . . . 488-489
limitations .................................. 13 Grass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392
See also Radioscopy Gray level . . . . .......... 468
Flux leakage. See Magnetic flux leakage Grease, as ultrasonic testing couplant . . . . . . . . . . . . . 402
572 I INDEX
Greinacker circuit, X-ray generators ... 104, 105 Hysteresis loops 279
Grid diaphragms 150, 151 for demagnetization 285
Grid spacing, in ultrasonic testing for sorting . 212
Grid testing 404
Grinding cracks . 497-498
Grounding
Gulton whistle 264
44-45
61
Illuminance . . . 21
H Illuminated magnifiers . 444-445
Illumination 440-441, 442
Image converters .. .... 177
Half-life .... 114, 115 Image enhancement
Half skip (V) test 405 in radioscopy 184-187
Half-wave direct current 281-282 in visual testing . 447-448, 468
Halitation 463 Image formation .. 426
Hall effect devices Image generation methods .. 16
eddy current testing .. 201 Image intensifiers 175-178
magnetic flux leakage testing .. 248 Image isocon tubes 180, 181
Halogen diode detector probe leak testing . 67-68 Image orthicon tubes 462
Halogen diode leak testing . . . . . . . . . . 40 Image quality indicators .. ................. 143, 166-169
Halogen tracer gas techniques . 34, 48 Image segmentation 468
H and D curves, radiographic films 161-163 Image sensors ...... 47-471
Hand probes, for magnetic particle testing .. 277 Image tubes 180, 181, 182, 470-471
Hardness testing 2 Immersion tanks 408
of automotive parts, by eddy current testing . 232-234, 236-237 Immersion ultrasonic testing . 353, 354, 357, 381
Heat affected zone cracks . ...... . 263 advantages . . ... 407
Heat transfer .. 478-482 composites 419-423
Heat treating cracks 264 coupling 407-410
Heat treatment devices for 408-410
camshaft inspection 237-238 discontinuity location . . . . . . . 410-414
eddy current monitoring . 200, 202 of rotor wheels (aircraft) . 414-418
permanent magnet creation by .. 268 test parameters .. 410-411
turbine rotor wheels . .... 418 Impact damage (composite discontinuity) 421, 422
and ultrasonic beam attenuation ..... 392 Impedance method, eddy current testing ... 203
Helium detector probe leak testing method .... 59 Impedance plane analysis, eddy current testing 212-217
Helium mass spectrometer leak testing 34, 37, 59-60, 68 Implosion hazards 46
for vacuum systems . 56 Industrial gas trailer tubing, acoustic emission testing 318-321
Helium tracer probe leak testing method 59 Infinite liftoff impedance .. 204
Helmholtz resonator 61 Infrared methods .. .... 16
High frequency ultrasonic transducers 372-373 Infrared radiation 92, 480-481
High luminance visible light sources, hazards of .... 436-437 hazards. . . . . 437, 438
High tension connections, X-ray generators 105-106 Infrared thermography .. 16, 474, 478-482
High voltage electric transmission systems, thermography 491 applications . . . 486-496
High voltage megavolt radiography 151 instrumentation/techniques . 482-485
Histogram equalization radioscopic image enhancement . 187 Ingot cracks 260
Hole penetrameters .. 166, 169 Ingots 259
Holography . 498-500 Inherent detector leak testing . 35
Homomorphic fdtering .. 187 Inherent discontinuities . 259-260
Hood method, of helium leak testing . 60 Inhomogeneous materials, ultrasonic wave propagation in 350
Hood, X-ray tubes 102, 103 Initial pulse, thickness gages 368
Horseshoe magnets 270, 271 Inspection 9
Hot tears .. 263 departments and 11
Hsu-Nielson source 302 management 12
Hubs (automotive), eddy current testing 236-237 receiving ..... 11
Huggenberger resistance strain gage ............ 506 responsibilities in . 7-8
Human eye. See Eye Inspectors
Hydrogen embrittlement 265 responsibilities 7-8, 12
Hydrophilic emulsifiers . 82 skills and judgment of 14
Hyperopia . . . . . . . . .............. . 429 Intensified silicon intensifier target (SIT) tube 180
Hyperthermia . . 437 Interface triggering . 367
Hysteresis Interferometry
magnetic . . 278-280 holographic .. 498-500
in strain gaging 508 moire 498
INDEX I 573
shearography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500 Lead zirconate titanate transducers . . . . . . . . . . . . . . . . . . . . 352-353
speckle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 498 Leakage rate . . . . . . . . . . . . . . . . . . . . . 26-28
Interlacing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183, 462 acoustic signal dependence on . . . . . . . . . . . . . . . . . . . . . . . . . . . 63-64
Internal conductor magnetization ............ . . . . . 273 bubble equivalents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Internal evaluation of parts, by X-ray computed conversion factors for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
tomography 188, 190-192 gas tracer measurement . . . . . . . . . . . . . . . . . . . . . . . . . 36
International Institute of Welding reference block . . . . . 397 minimum detectable . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
International Organization for Standardization (ISO) pressure change tests for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50-53
film speeds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 447 and pressure differential . . . . . . . . . . . . . . . . . . . . . . . . . . . · 27
ISO 1000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 quantitative description . . . . . . . . . . . . . . . . . . . . . . . . . . .. 27-28
ISO 9712 80 and serviceability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
International Radiation Protection Association . . . . . . . . . . . . . . 437 units . ........ 27, 28
Interpretation of results, limitations on . . . . . . . . . . . . . . . . . . . . . 13 vacuum systems . .... 28
Intrinsic moire method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 497 Leak conductance . 27
Inverse square law, and radiography . . . . . . . . . . . . . . . . . . . . . . 139 Leak location . . . . . . . . . . . . . . . . 32, 34-35
Ionization chamber meter ................. . . . . . . . 113 coordinating with leakage rate measurement . 38-39
Iridium-192 . . . . . . . 115, 116-118, 145 electronic detectors for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Iris . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429 individual leaks . 38
ISO. See International Organization for Standardization (ISO) method sensitivities compared . . . 39
Isocon tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180, 181 Leaks................ .. . . .. . . . 26
Isotopes. See Radiographic isotope sources acoustic characteristics . . . . . . . . . . . . . . . . . . . 61, 63
flow modes through . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
J reference leaks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Leak testing . . . . . . . . . . . . . . . . . . . . . . . . 25-74
applications . . . . . . . . . . . . . . . 26, 28-29, 32, 33
Jaeger eye chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 430, 431 categories of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32-34
Jet engine burner, video borescope inspection . . . . . . . . . 460 leak detectors . . . . . . . . . . . . . . .............. 31
J fasteners, X-ray computed tomographic evaluation
191 fluid media used for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32, 34
Joints impractical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
leak testing . 28-29, 50, 54-55 individual leaks 26-27, 38
See also Welded joints laser application . . . . . . . . . . . . . . . . . . 39-40
Journals, fatigue cracking .......................... 266 leak detectors . . . . . . . . . . . . ............ 31
locating all leaks . . . ............ 29-30
K method selection decision tree . . . . . . . . . . . . 32, 33, 35-36
open test objects, accessible on both sides . . 36-37
K absorption edge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 personnel training . . . . . . . . . . . . . . . . . . 40-41, 43
Kaiser effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302-303, 304 safety aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42-47
Klien-Nishina formula . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 sensitivity-cost relationship . . . . . . . . . . . . . . . . . . . . . . 32
Knot (composite discontinuity) 421 sensitivity for practical applications . . . . . . . . . . . . . . . . . 30-32
SNTTClA and . . . . . . . . . . 40-41
standard conditions for 31
L storage tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65-69
systems leaking to atmosphere 37-38
Labor .7 units for . . ................. 20-21
Lack of fusion/penetration weld discontinuities . . . . . . . . . . . . . . 263 vacuum systems. See Vacuum systems, leakage rate/testing
See also Acoustic leak testing; Bubble leak testing; Helium mass
Lack of rovings (composite discontinuity) 421, 422 spectrometer leak testing; Mass spectrometer leak testing
Lamb waves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396 Leak tightness . ................... 29-30
Laminate composites 419, 423 Lenses
See also Composites for optical coupling in radioscopy . . . . . . . . . . . . . . . . . . . . . . . . . . 182
Laminations 261 ultrasonic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 390-392
Lampblack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 482, 484 with ultrasonic transducers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 354
Laps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261, 262 Liftoff curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Laser applications Liftoff effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202
holography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 498-500 and impedance plane .. 213-217
leak testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39-40 Light amplifiers .. 177
point triangulation profilometry . . . . . . . . . . . . . . . . . . 500-502 Light guides ..... .. 450
shearography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500 Lighting .. . 440
ultrasonic testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 370-371 machine vision systems 468-470
Laser eye protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 439 photography .. 446
Laser hazards . . . . . . .............. 436 Light intensity 440-441
Lead foil screens 147-148, 151, 152-154 Light sources 426
and graininess . . . 166 hazards 436-438
574 I INDEX
Limited angle computed tomography . . . . . . . . . . . . . . . . . 190 Magnetic particles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249-250, 258
Linear accelerators 107, 108 dry powder 289, 290-291
Linear elastic waves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350 fluorescent 289, 291
Line focusing 100 mobility 290-291
Lines of forces, magnetic fields . . . . . . . . . . . . . . . . . . . . . . . . . . . 267 particle shape effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289-290
Lipophilic emulsifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 particle size effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289
Liquid film bubble leak testing 57-58 properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288-289
Liquid penetrant developers . . . . . . . . . . . . . . . . . . . . . . . . . 77, 82-83 visibility/contrast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290
Liquid penetrants 76, 81-82, 83 wet method 289, 290, 291
Liquid penetrant testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76-88 Magnetic particle testing . . . . . . . . . . . . . . . . . . . . . . . . . . 76, 257-295
advantages/disadvantages of . . . . . . . . . . . . . . . . . . . . . 13, 78- 79, 85-86 capabilities/limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77-78 demagnetization . . . . . . . . . . . . . . . . . . . . . . . . . 258, 269, 282, 284-287
automated inspection systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 discontinuity types and . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259-266
equipment for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79-80 orientation effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272
history of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 subsurface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271
part protection after testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87-88 equipment for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276-277
personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
process description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76- 77, 86-88 magnetizing current 281-283
process selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84-85 media selection 291
sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 mobile/portability test systems . . . . . . . . . . . . . . . . . . . . . 276-277
Lithium niobate crystals . . . . . . . . . . . . . . . . . . . . . . . . . . . . 354 processes 291-292
Lithium sulfate monohydrate crystals . . . . . . . . . . . . . . . . . . 352, 354 sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Load transducers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 508 units for 21, 278
Logarithmic processing radioscopic image enhancement . . . . . 187 Magnetic permeability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280, 288
Longitudinal magnetization 270-271, 274 Magnetic poles '. . . . . 267-268, 270
Long pass optical filters 470 Magnetic recording tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Lorentz forces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373 Magnetic resonance imaging (MRI) . . . . . . . . . . . . . . . . . . . . . . . 504
Low frequency ultrasonic transducers 371-372 Magnetic saturation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
Low modulus fibers (composite discontinuity) 421, 422 Magnetism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268-269, 270
Low power microscopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 445-446 electrically-induced . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273-275
Luminance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 mechanically-induced . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
Luminous energy tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 426 residual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278, 280
units for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21, 178
Magnetization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
M circumferential 273-274
internal conductor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
longitudinal 270-271, 274
multidirectional '. 275
Machinery, increased demands on . . . . . . . . . . . . . . . . . . . . . . . . . 6-7 Magnetizing current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281-283
Machine shops, borescope application . . . . . . . . . . . . . . . . . 452-453 Magnetodiodes . 248, 249
Machine vision technology . . . . . . . . . . . . . . . . . . 468-471 Magnification
Machining tears . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263 borescopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 454
Macroscopes, wide field . . . . . . . . . . . . . . . . . . . . . . . . . . . 446 video cameras . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 464
Magnetic Barkhausen effect method . . . . . . . . . . . . . . . . . . . 505 Magnifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 443-445
Magnetic domains 267,268 Manufacturing
Magnetic fields . . . . . . . . . . . . . . . . . . . . . . . . . 267-269 cost reduction with nondestructive testing . . . . . . . . . . . . . . . . . . . . 5-6
circular . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270 discontinuities of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259, 263-265
right hand rule for 274 Masks, radiographic 148
Magnetic field strength . . . . . . . . . . . . . . . . . . . . . . 271 Mass flow rate (in leak testing). See Leakage rate
Magnetic flux 267, 278 Mass spectrometer leak testing . . . . . . . . . . . . . . . . . . . 40
Magnetic flux density . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270, 278 for vacuum systems . . . . . . . . . . . . . . . . . . . . . . . . . . . 55-56
Magnetic flux leakage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242, 258 See also Helium mass spectrometer leak testing
Magnetic flux leakage fields . . . . . . . . . . . . . . . . . . . . . 270 Match band effect . 447
Magnetic flux leakage testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242 Material composition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 17
applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250-253 of automotive parts, eddy current testing . . . . . . . . . . . . . . . . . 232, 233
pipeline . . . . . . . . . . . . ............ . . . . 252-253 Material flaws
steel industry . . . . . . . . ............. . . . . . . . . . . . 218 internal evaluation by X-ray computed tomography 188, 190-192
tubing . . . . . . . . . . . 250-251 leak testing evaluation . . . . . . . . . . . . . . . . . . . . . . . 28-29
wire ropes ... 251-252 radioscopic detection . . 186
part types inspectable 142-246 See also Crack detection; Discontinuity detection; Leaks
sensors for . . . . . . 246-250 Material properties
Magnetic hysteresis. See Hysteresis eddy current testing . . .................. 200, 202
Magnetic materials ..... 268 and material behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 475, 477
INDEX I 575
testing methods 13, 16, 17 Naval Submarine Medical Research Laboratory, color vision
Materials classification scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 433-434
anisotropy 349, 350 NDT. See Nondestructive testing
demand for sounder materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Nearsightedness 429
inservice inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Near vision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429
limitations on methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Near vision examinations 430
See also Composites; Ferromagnetic materials Neighborhood processing radioscopic image enhancement . . . . 184
Materials engineer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Neutral density optical filters 470
Matrix structure determination . . . . . . . . . . . . . . . . . . . . . . . . . 16, 17 Neutron absorption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Mcclurg formula . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250 Neutron generators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
Measure, units of. See SI units Neutron irradiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Measuring magnifiers . . . . . . . . . . . . . . . . . . . . . . . . . 444, 445 Newvicon cameras . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180
Mechanical joints. See Joints Nonaqueous penetrant developers . . . . . . . . . . . . . . . . . . . . . . . . . 83
Mechanically induced magnetism . . . . . . . . . . . . . . . . . . . . . . . . . 269 Noncontact ultrasonic testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 370
Mechanical-optical methods 16 Nondestructive characterization 474
Mechanical properties 16, 17 Nondestructive evaluation. See Nondestructive testing
Medical nondestructive testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Nondestructive examination. See Nondestructive testing
Medical tomography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188 Nondestructive inspection. See Nondestructive testing
Membranes, for coupling in contact ultrasonic testing .... 400-401 Nondestructive characterization 2, 474, 476
Metals Nondestructive testing
alloy identification 474,475,503,504 applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6, 15
eddy current testing. See Eddy current testing defined 2
Kaiser effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302-303, 304 developments leading to rapid growth and acceptance of . . . . . . . . . 6-8
radiation absorption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 engineer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
radiographic equivalence factors . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 future usefulness of parts and . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
as radiographic filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 glossary of terms : 515-564
ultrasonic beam attenuation by . . . . . . . . . . . . . . . . . . . . . . 392 information sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
See also Aluminum; Steel limitations on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-14
Metric system. See SI units method classification 15-16, 476
Metrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 17 objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Microchannel arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177 vs. attributes measured . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Microfocus X-ray sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 as panacea . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Microscopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 443, 445-446 policies for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-12
television application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 459 properties measured: limitations on number . . . . . . . . . . . . . . . . . . . 13
Microseismic activity. See Acoustic emission reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Microstructure determination . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 17 scheduling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-15
Microwave testing 476, 505 sensitivity/accuracy specification . . . . . . . . . . . . . . . . . . . . . . . . . . 12-14
MIL-1-25135 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 sensitivity range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Miniborescopes 451-452 SI units for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18-22
Minimum detectable leakage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 special methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... 474-477
Mirrors, for optical coupling in radioscopy . . . . . . . . . . . . . . . . . 182 specification of tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-17
Modulation transfer functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186 visual aspects of methods . . . . . . . . . . . . . . . . . . . . . . . . . . . 426
Moire 497 See also Inspection
Moire interferometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 498 Nonfluorescent colored penetrants . . . . . . . . . . . . . . . . . . . . . . . . . 76
Moire testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 497-498 Noninvasive medical diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Moisture detection (buildings) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 490 Nonlinear elastic waves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350
Monochromatic X-radiation . . . . . . . . . . . . . . . . . . . . . . . . 93-94 Nonmetallic inclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
Monochromators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 426 North poles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
Multidirectional magnetization . . . . . . . . . . . . . . . . . . . . . . . . . . . 275 Nuclear magnetic resonance imaging (NMRI) . . . . . . . . . . . . . . . 504
Multifrequency eddy current testing . . . . . . . . . . . . . . . . . . . 239-241 Nuclear power plants, borescope application 453, 461
Multiple acoustic emission sensors . . . . . . . . . . . . . . . . . . . . . . . 62-64 Nugget formation, in spot welding . . . . . . . . . . . . . 324, 327, 329-330
Multiplier phototubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 458
Mushroom eddy current probes . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Myopia 429 0
N Occupational Research Center, vision acuity examination slides 431
Oil-and-whiting penetrant method . . . . . . . . . . . . . . . . 76
National Materials Advisory Board Ad Hoc Committee on Oils, as ultrasonic testing couplant . . . . . . . . . . . . . . . . . . . . . 402
Nondestructive Evaluation, methods classification Oil well casings. See Well casings
scheme . . . . . . . . . . . . . . . . . . . . . . 15-16 Optical coupling . . . . . . . . . 182-183
7
National Safety Council Optical filtering . . . . . . . . . . . . . . . . . . . . . . 470
576 I INDEX
Optical testing . . . . . . . . . . . . . . . . . . . . . 426, 497-502 Pinchwelds, on undersea repeaters, acoustic emission
safetyaspects . . . . . . . . . . . . . . . . . . . . . . . . . 435-439 testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 334-336
SI units 21 Pinion gears (automotive), eddy current testing . . . . . . . . . . 235-236
See also Visual testing Pipe (discontinuity type) 259-260
Optical units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Pipelines
Optics . 426-427 acoustic leak testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Overstress cracking . . . . . . . . . . . . . . . . . . . . . . . 266 magnetic fluxleakage testing . . . . . . . . . . . . . . . 243-244, 252-253
Oxtails . . .... 103 Pipes
fiber-reinforced plastic, acoustic emission testing 312-314
p remote field eddy current testing of walls . . . . . . . . . . . . . 206, 207-211
rotating pipe eddy currenttesting system . . . . . . . . . . . . . . . . . 220-222
threads, magnetic fluxleakage testing . . . . . . . . . . . . . . . . . . . 245, 246
visual testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 465, 466
Pair production, high energy photons . . . . . . . . . . . . . . . . . . . . . . 97 See also Tubes
Panoramic borescopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 452 Piston rods, forging laps . . . . . . . . . . . 263
Paramagnetic materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268 Pitch and catch ultrasonic transducer
Partial volume effects . . . . . . . . . . . . . . . . 195 configuration 354,356,380,396
Particle accelerators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 Pitting . . . . . .............. . . . . . . . . . . . . . . 266
Passive infrared thermography . . . . . . . . . . . . . . . . . . . . . . . 482, 484 Planck's Distribution Law . . . . . . . . . . 481
Pavement, thermography . . 491-492 Plastic deformation . . . . . . . . . . . . . . . . . . . . . . . . 477
Pencil eddy current probes . . . . . . . . . . . . . . . . . . . . 204 acoustic emission and .............. 298
Penetrameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143, 166-169 Plating cracks .................. 264-265
Penetrants. See Liquid penetrant testing Plumbicon cameras . . . . . . . . . . . . . . . . . . . . 180
Penetrating radiation methods. See Radiography Ply gap (composite discontinuity) . . . . . . . . . 421
Peripheral vision . . . . . . . . . . . . . . . . . . . . . 432 Point processing radioseopic image enhancement . . . . . . . . . . . 184
Permanent magnets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268 Point triangulation proftlometry . . . . . . . . . . . . . . . . . . . . . . . 500-502
Permeability (magnetic) . . . . . . . . . . . . . . . . . . . . . . 280, 288 Polycrystalline ceramics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 352, 354 :,.
Personnel monitoring, in radiography . . . . . . . . . . . . . . . . . . . . . 112 Portable testing apparatus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Personnel training. See Training Positioning and transport systems . . . . . . . . . . . . . . . . . . . . . . . 465
Petroleum industry Postemulsifiable penetrants 81-82, 84, 85
borescope application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 453 Pot core eddy current probes . . . . . . . . . . . . . . . . . . . . . . 204
See also Pigs; Pipelines; Well casings Potential drop testing. See Resistivity testing
Phase vectors . . . . . . . . . . . . . . . . . . . . . . . . . . 212-213 Potter-Bucky diaphragm . . . . . . . . . . . 150, 151
Phasor diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212-213 Potting compound . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105-106
Photoconduction . 462 Power packs, for magnetic particle testing . . . . . . . . . . . . . . . . . . 276
Photoconductive cells 457 Power plants, borescope application . . . . . . . . . . . . . . . . . . . 453, 461
Photoconductive lag 458 Preamplifiers, for acoustic emission testing 301-302
Photocurrent signal 178 Preattentive processing . . . .............. 428
Photodiodes Pressure change leak testing . . . . . . . . . . . . . . . . . . . . . . . . . 40, 50-53
arrays . . . . . . . . . . . . . . . . . . . . . . . . . 178-179 Pressure coupling .......... 402
visualtesting application . . . . . . . . . . . . . . . . . . . . . . . . . . . 457 Pressure units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20, 51
Photodisintegration . . . . 95, 97 Pressure vessels
Photoelastic coatings . . . . . . . . . . . . . . . . . . . . . . . . . . 475 acoustic emission testing . . . . . . . . . . . . . . . . . . 299, 300, 310-317
Photoelastic stress analysis . . . . . . . . . . . . . . . . . . . . . . . . . . 507 leak testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46, 52
Photoelectric devices 457, 458-459 visualtesting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 453
Photoelectric effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95-96 Primary processing discontinuities . . . . . . . . . . . . . . . . . 259, 260-262
Photoemission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 462 Principal plane of focus . . . . . . . . . . . . . . . . . . . . 446
Photoemissive devices . . . . . . . . . . . . . . . . . . . . . 457 Probes
Photographic density, radiographic films 158, 159 for eddy current testing . . . . . . . . . . . . . . . . . . . . . . . . . 200, 204
Photographic films . .............. 447 for magnetic particle testing . . . . . . . . . . . . . . . . . . . . . . . . 277
Photography . . . . . . . . . . . . . . . . . . . . . . . . . 446-447 Probe transducers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224
with borescopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455-456 Process engineer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Photons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92, 435 Prods 277
absorption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95-96 Product design, role of nondestructive testing in . . . . . . . . . . . . . . 5
scattering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95, 96-98 Product failure analysis, by X-ray computed tomography .. 195-196
Photosensitizers . . . . ............ . . . . . . . . 438 Product reliability. See Reliability (product)
Phototubes . . . . ............ . . . . . . . 458 Projected moire method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 497
Photovoltaic cells . . . . . . . . . . . . . . . . . . . . . . . . . 457-458 Proof testing 2, 51-52
Physical properties . . . . . ......... ..... 16, 17 Proportional elastic behavior 477
Pickling cracks . . . . . . . . . . . . . . . . . . . . . . 264-265 Prototype evaluation, by X-ray computed tomography 195-196
Pickup coils . . . . . . . . . . . . . 246-247 Pseudocolor ........... . . . . . . . . . . 187
Piezoelectric transducers . 352, 365 Pseudo sources, of acoustic emission 298
Pigs . . . . . . . . 252 Pulse echo ultrasonic testing. See Ultrasonic pulse echo testing
INDEX I 577
Pumping speed, vacuum systems . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Radiographic testing. See Radiography
Pyrometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 482
Radiographs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132, 170-171
Radiography 132-133
applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132-133
a computed tomography 188-196
vs. film radiography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188-189
diffraction mottling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
QPL-25135 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 exposure chart 159-160
Quality assurance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-10 image interpretation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169
role of nondestructive testing in . . . . . . . ............. 6 image quality 164-169
Quality control 9, 10 limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Quality levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6, 10 milliamperage-distance relationship 139-140, 141
Quality specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10, 11 milliamperage-time relationship : 140, 141
Quartz crystal transducers . . . . . . . . . . . . . . . . . . . . . . . 352 penetrating radiation methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Quasilongitudinal elastic waves . . . . . . . 350 radiation absorption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144-146
Quasishear elastic waves . . . . . . . . . . . . . . . . 350 radiation scattering . · 146-150
Quench cracking . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 real time. See Radioscopy . . . . . . . . . . . . . . . . . . 174
reciprocity law . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140-141
safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
R setup diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
shadow formation: geometric principles of 134-139
distortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135-136
enlargement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134, 138
R-12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 geometric unsharpness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136-138
R-22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 inverse square law . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
R-134a . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 rules for successful . . . . . . . . . . . . . . . . . . . . . 135, 136
Radar 505 SI units for , . , , . . . . . . . . . . . . . . . . . . . . . . 18-20
See also Microwave testing time-distance relationship 140
Radiation. See also Electromagnetic radiation X-ray computed tomography 188-196
heat transfer 478, 480-482 vs. film radiography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188-189
methods of nondestructive testing . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 See also Radioscopy; X-ray computed tomography; X-ray Generators
shielding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112, 122, 123 Radiometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 482-485
Radioactive Materials, Regulations for Safe Transport of . . . . . . 116 Radioscopy 174-187
Radioactivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 image enhancement techniques 184-187
Radiographic exposure devices image intensifiers for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175-178
classification . . . . . . . . . . . . . . 120-122 optical coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182-183
manual source manipulation ..... 120 remote viewing system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176, 183
remote handling equipment . 120-127 spectral matching of phosphors and photocathodes . . . . . . . . . 177-178
See also X-ray exposure system setup . . . ................. . . . . . . . . . 175
Radiographic contrast 142, 164-165 television cameras for . . . . . 178-182
Radiographic diaphragms/masks . . . . . . . . . . . . . . . . . . . . . . 148, 150 viewing/recording systems . . . . . . . . . . . . . . . . . . . . 176, 183
Radiographic equivalence factors 144, 145 Radio waves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Radiographic exposure factors . . . . . . 133-134, 137, 141-142, 159-160 Radium-226 . . . . .. , .. , . . . . 114
Radiographic films 132, 157-163 Rare earth phosphors ..... 177
characteristic curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161-163 Raster . . . . . . . . . . . . . . . . . . . . . . . . . . . . 461-462
graininess . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 Raw material inspection . . . . . . . . . . . . . . 15
handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170 Rayleigh waves . . . . . . . . . . . . . . . . . . . . . . . . . . . . 349-350
photographic density . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158, 159 Readers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 443-444
selection 142-143, 158 Real time radiography. See Radioscopy
storage . . . . . . . . . . . .............. 170-171 Real time radiometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 483
Radiographic filters . . ............ . 148-150 Receiving inspections . . . . . . . . . . . . . . . . . . . . . . 11
Radiographic isotope sources 114-119, 133-134 Reciprocity law, radiography . . . . . . . . . . . . . . . . . . . . 140-141
characteristics of widely used . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 Reference leaks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
handling equipment 120-127 Reflected moire method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 497
handling regulations/requirements . . . . . . . . . . . . . . . . . . . . . . . . . . 116 Reflection ultrasonic testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 351
Radiographic screens 147-148, 151, 152-156 Reflector plates, use in immersion ultrasonic testing . . . . . . . . . 420
and contrast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 Refrigeration equipment, leak testing . . . . . . 35
functions of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152 Regulations for Safe Transport of Radioactive Materials . . . . . . . 116
and graininess . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 Reliability, of nondestructive testing methods 14
screen mottle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155, 166 Reliability (product) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5, 9
Radiographic sensitivity . . . . 10, 143, 164 assurance through nondestructive testing . . . . . . . . . . . . . . 3-5
factors controlling . . . . . . . . . . . . . . . . . . 165 See also Quality assurance
Radiographic shadows . . . 134-139 Reliability (system), leakage testing . . . . . 26, 28
578 I INDEX
Remanance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278 Second generation image converters . . . . . . . . . . . . . . . . . . . . . . 177
Remote field eddy current testing 206-211 Sensitivity specification 12-14
Remote positioning and transport systems . . . . . . . . . . . . . . 465-467 Separations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 17
Repeaters, undersea, acoustic emission testing 331-336 See also Discontinuities
Residual gas analyzers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55-56 Serviceability, leakage rate and . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Residual magnetism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278, 280 Service damage, limitations on testing for 14
Residual stress cracking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 Service discontinuities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259, 266
Residual test method, of magnetic particle testing 291-292 Shades (eye protection) 439
Resins, as ultrasonic testing couplant . . . . . . . . . . . . . . . . . . . . . . 402 Shadow formation, in radiography 134-139
Resin starved layer (composite discontinuity) 421, 422 Shadow moire method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 497
Resistance spot welding, acoustic emission monitoring 323-330 Shafts, automotive axle shaft eddy current testing . . . . . . . . 232-234
Resistance strain gaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 506-508 Shake and bake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 505-506
Resistivity (potential drop) testing 212, 476, 503-504 Shape limitations, on methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
measurement units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Sharpness, of radiographic images . . . . . . . . . . 134, 136-138
Resonance transformers, for X-ray generators . . . . . . . . . . . . . . 106 Shearography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500
Responsibility, in inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8 Shear wave angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397
Retentivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268, 278 Shielding (radiation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112, 123
Retina . . . . . . . . . . . . . 429, 432 Shrinkage cracks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263
damage to . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 436, 438 Sight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 428-429, 432-434
Retrospective borescopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455 Signal image analysis methods 16
Return trace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 461, 462 Signal value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317
Reverse engineering, by X-ray computed tomography . . . . . . . . 195 Signature analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 17
Right angle borescopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455 Silicon diode tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180
Right hand rule, for magnetism . . . . . . . . . . . . . . . . . . . . . . . . . . . 274 Silicon intensifier target tube . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180
Rigid borescopes . . . . . . . . . . . . . . . . . . . . . . 450-452 Single-phase full-wav~ direct current . . . . . . . . . . . . . . . . . . . . . . 282
Ringing technique, for contact ultrasonic testing . . . . . . . . . 402-403 Sistering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 467
Robotic camera transport systems . . . . . . . . . . . . . . . . . . . . . 465, 466 SI units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18-22
Rocket motors, internal evaluation by X-ray computed conversions for obtaining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
tomography 195 derived 18
Rock noise. See Acoustic emission for nondestructive testing methods
Rod anode, X-ray tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 electrical and magnetic testing . . . . . . . . . . . . . . . . . . . 21
Rods (eye) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429 leak testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-21, 26-28
Rotating cast round billets, eddy current testing . . . . . . . . . . . . . 225 optical 21
Rotating pipe inspection system . . . . . . . . . . . . . . . . . . . . . . . 220-222 radiography . . . . . . . . . . . . . . . . . . .......... 18-20
Rotational soldering, of undersea repeaters 331, 332 vs. decibel 21-22
Rotor wheels (aircraft), immersion ultrasonic testing of 414-418 prefixes for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Round bar inspection system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220 table of . . . . . . . . . . . . . . . . . . . . . . 18
Rounding off 21 Size limitations, on methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Skin depth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205, 208
s Skin effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204-205, 281
Slabs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259
SNTTCIA, ASNT Recommended Practice No.
and leak testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40-41
and liquid penetrant testing . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Safety Society of the Plastics Industry (SPI), vessel acoustic
leak testing 42-47 emission testing procedure 310, 311, 317
optical/visual testing . . . . . . . . . . . . . . . . . . . . . . . . . . 435-439 Societies that issue acoustic emission standards . . . . . . . . . . . . . 299
public demands for increased . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Solid state cameras 178-180
radiographic source equipment . . . . . . . . . . . . . . . . . . . . . . . . . 122-127 Solid state image amplifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 458
X-ray generators . . . . . . . . . . . . . . . . . . . . 112-113 Solid state imaging devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 471
Sampling 2 Solvent removable penetrants . . . . . . . . . . . . . . . . . . . . . . . . 82, 85-86
Saturation point . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278 Solvent removers, use in liquid penetrant testing . . . . . . . . . . . 82
Scabs . . . . . . 263 Sonic-ultrasonic methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Scanning, in television systems 461-462 See also Acoustic nondestructive testing methods
Scanning limitations, on methods . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Sorting, eddy current techniques for . 212-217
Scanning radiometry . . . . . . . . . . . . . . . . . . . . . 483 Sound units . . . . . . . . . . . 21-22
Scattering, of radiation 95, 96-98, 146-150 Sources. See Radiographic isotope sources
Scheduling tests 14-15 South poles . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
Screen effect, X-ray tubes 100-101 Spallation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Screen mottle 155, 166 Special methods of nondestructive testing. . . . . . . . . . . 473-513
Seams 260-261 Speckle techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 498
Secondary processing discontinuities . . . . . . . . . . . . . 259, 263-265 Spectrum, electromagnetic . . . 92, 434, 480
Secondary sources, of acoustic emission . . . . . . . . . . . . . . . . . . . . 298 Spindles (automotive), eddy current testing 236-237
INDEX I 579
Spot welding, acoustic emission monitoring . . . . . . . . . . . . . 323-330 T
Springs, pickling cracks in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
Standard physical leaks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Standards, cost of inadequate 14
Standoffs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 401 Tap testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 505
Static electricity, hazards with flammable materials . . . . . . . . . . . 44 Targets, X-ray tubes 101-102
Static leak testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36, 37 Tear discontinuities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262, 263
Steady state heat conduction 478, 479 Television camera tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 462
Steam power plants, borescope application 453, 461 Television holography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 498
Steel Television systems
ball bearings, magnetic flux leakage testing . . . . . . . . . . . . . . . . . . . 245 radioscopy application . . . . . . . . . . . . . . . . . . . . . . . . . 178-182
bar inspection systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218-222 remote positioning and transport systems . . . . . . . . . . . . . . . . . 465-467
bolt hole eddy current testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231 resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 463-464
discontinuities of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259-266 scanning principles 461-462
eddy current testing 214, 215, 218-227 underwater lamps for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 464
high temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223-227 visual testing application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 458-459
free machining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260 Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9, 10
grain size discontinuities 413-414 See also Nondestructive testing
pipe walls, remote field eddy current testing of . . . . . . . . . . . . 209-210 Thermal testing 16, 478
radiography . . . . . . . ... 145, 146, 150, 153, 154, 156 thermal vs. infrared 478
contrast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 See also Infrared thermography
films for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158, 159, 160, 161 Thermal diffusivity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 479
radioscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185 Thermal transfer imaging system . . . . . . . . . . . . . . . . . . . . . . . . . 493
spot weld acoustic emission monitoring . . . . . . . . . . . . . . . . . . 327-329 Thermoelectric techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212
thermography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 495-496 Thermography. See Infrared thermography
ultrasonic beam attenuation by . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392 Thermoluminescent dosimeters . . . . . . . . . . . . . . . . . . . 112, 127
See also Ferromagnetic materials Thickness gages . . . . . . . . . . . . . . . . . . . . . . . . . . 13, 364, 365, 368-369
Stefan-Boltzmann Law 480-481,483 Thickness measurement, by ultrasonic testing 347, 352
Stepping pipe crawlers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 465 Three-phase full-wave alternating current . . . . . . . . . . . . . . . . . . 282
Storage tanks, leak testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65-69 Three-phase full-wave direct current . . . . . . . . . . . . . . . . . . . 282-283
Straight beam pulse echo ultrasonic testing . . . . . . . . . . . . . 382-396 Throughput, vacuum systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Straightening cracks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 Through-transmission ultrasonic testing . 351, 352, 354-356, 357, 396
Strain 475, 477 Thulium-170 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115, 118
Strain gage transducers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 508 Time-of-flight measurements 411, 419-420
Strain measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 474, 497-500 Timing section, ultrasonic testing equipment . . . . . . . . . . . . . . . . 365
resistance strain gaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 506-508 Titanium bolt holes, eddy current testing 231
Stress 475 Tolerance specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Stress corrosion cracking . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246, 266 Tomography, X-ray computed. See X-ray computed tomography
acoustic leak characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Toxic gases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
ultrasonic imaging of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 406 Trace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 461, 462
See also Crack detection Tracer probe techniques . . . . . . . . . . . . . . . . . . . . . . . 34-35, 36, 48-49
Stress cracking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266 safety aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Stress engineer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Training
Stress measurement 474, 505 acoustic emission testing . . . . . . . . . . . . . . . . . . . . . . . . . 302
Stress response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 17 leak testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40-41, 43
Stress wave emission. See Acoustic emission liquid penetrant testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Stress wave factor technique . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 506 ultrasonic testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 346
Stringers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260 visual testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 441
Strobe lighting 426-427, 469-470 Transformers, for X-ray generators . . . . . . . . . . . . . . . . . . . . . . . . 106
Structural flaws . . . . . . . . . . . . . . . . . . 16, 17 Transient heat transfer 478-479
Structure determination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 17 Transmit-receive method, of eddy current testing . . . . . . . . . . . 203
Structured lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 469 Transmit/receive switch, ultrasonic testing equipment . . . . . . . . 365
Subject contrast, in radiography 164, 165 Transmittance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Submarines, autonomous . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 465 Transverse discontinuity inspection, by magnetic flux
Subsurface discontinuities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271 leakage testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250-251
Subterranean surveys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 492 Tube gamma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180, 181
Subtraction operations, in radioscopic image enhancement . . . 185 Tubes
Summation operations, in radioscopic image enhancement 184-185 angle beam contact ultrasonic testing . . . . . . . . . . . . . . . . . . . . . . . 398
Supersonic reflectoscope . . . . . .......... 349 boiler, visual testing . . . . . . 453, 461
Surface coil eddy current transducers . . . . . . . . . . . . . . . . . . . . . 204 composite, immersion ultrasonic testing . . . . . . . . . . . . . . . . . . 420-422
Surface comparators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 444 magnetic flux leakage testing . . . . . . . . . . . . . . 250-251
Synchrotrons . . . . . . . . . . . . . . . . . . . . . . . ... ·. . . . . . . 106, 107 remote field eddy current testing of walls . . 206, 207-211
System Internationale (SI) units. See SI units See also Pipes
580 I INDEX
Tuhulation pinchwelds, on undersea repeaters, acoustic Ultrasonic wave propagation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 349
emission testing . . . . . . . . . . . . . . . . . . . . . . . . . . . 334-336 Ultraviolet borescopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 452
Tuckerman resistance strain gage . 506 Ultraviolet light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92, 434, 435
Turbines hazards . . . . . . . . . . . . . . . . . . . . . . . . . 437-438
blades, X-ray computed tomographic evaluation 190, 191, 195 Ultraviolet lighting 470
rotor wheels, immersion ultrasonic testing of . . . . . . . . . . . 414-418 Undercut . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146, 148, 150
Type 1 radiographic exposure devices 120-122 Underground storage tanks, leak testing . . . . . . . . . . . . . . . . . . . . 65
Type 2 radiographic exposure devices 120-122 Undersea electronic repeaters, acoustic emission testing 331-336
Underwriters Laboratories . . . . . . . . . . . . . . . . . . . . ........ 7
Units. See SI units
u Uranium
absorption curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
gamma radiography shielding material . . . . . . . . . . . . . . . . . . . . . . . 122
U-core eddy current probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Ultimate strength . . . . . . . . . . . . . . . . . . . . . . . . . . . 266 v
Ultrasonic attenuation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350
by scattering . . . . . . . . . . . . . . . . . . . . . . . . . . 392-393
Ultrasonic leak detection . . . . . . . . . 61-62
Ultrasonic lenses . . . . . . . . . . . . . . . . . . . . . . . 390-392 Vacuum : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Ultrasonic pulse echo testing . . . . . . . . . . . . . 351, 352, 356-357, 360 Vacuum box bubble leak testing . . . . . . . . . . . . . . 58, 66-67
advantages/disadvantages . . . . . . . . . . . . . . . . . . . . . . . . . . . 380 Vacuum box liquid penetrant leak testing . . . . . . . . . . . . . . . . . 66-67
coupling media for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400-403 Vacuum box penetrant developer leak testing . . . . . . . . . . . . . . . . 67
focused beam immersion testing . . . . . . . . . . . . . . . . . . . . . . . . 390-392 Vacuum systems ...... , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52, 54
imaging procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 404-406 leakage rate/testing . . . . . . . . . . . . . . . . . . . . . . . . . 28, 35, 52-53, 55-56
straight beam tests ....................... 382-396 pressure measurement in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
applications ........................ 384-388 Vacuum ultraviolet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 437
test frequency selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 393-394 Vacuum vessels, acoustic emission testing . . . . . . . . 312
See also Immersion ultrasonic testing Validity, of tests . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Ultrasonic reflection techniques Van de Graaff generators . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106, 107
size limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Vaporproofborescopes 452
Ultrasonic testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 345-424 Ventilation, in leak testing . . . . . . . . . . . . . . . . . . . . . . . . . 43-44
advantages 346-347, 352 Verification test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51-52
applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 347 Vessels. See Pressure vessels; Vacuum vessels
A-scan presentation . . . . . . . . . . . . 356-358, 380, 381, 392, 395 Vibration analysis . . . . . . . . . . . . . . . . . . . . .. 505
B-scan presentation 356, 358-359, 380, 381, 395 Video
calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 359-361 borescopes 459-461, 466
criteria for successful . . . . . . . . . . . . . . . 348 holography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 498
C-scan presentation . . . . . . . . . . . . . . . . . . . . . . 356, 359, 380-381, 395 radiometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 482-483
equipment for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363-369 systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 457-464
gated system display . . . . . . . . . . . . . . . . . . . . . . . . . . . . 356, 359 remote positioning/transport . . . . . . . . . . . . . . . . . . 466-467
immersion method. See Immersion ultrasonic testing See also Television systems
large testing systems ........... . . . . 369 tape recorders
laser application 370-371 radioscopy application 183
limitations 252, 347-348 visual testing application . . . . . . . . . . . . . . . . . . . . 466
portable systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 364-366 Vidicon cameras/tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . 179, 180, 181
pulse echo. See Ultrasonic pulse echo testing visual testing application 458-459, 462, 470-471
system parameters 361-362 X-ray sensitive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182
through-transmission systems 351, 352, 354-356, 357, 396 Vignetting . . . . ............. . . . . . . . . . . . . . . . . . 182
transmission vs. reflection techniques . . . . . . . . . . 3451 Villard circuit, X-ray generators . . . . . . . . . . . . . . . . . . . . . . . 104, 105
See also Acoustic nondestructive testing methods; Sonic-ultrasonic Virgin curve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
methods
Ultrasonic testing couplants . . . . . . . . . . . . . . . . . . . . . . . . 402 Visible light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Ultrasonic transducers . . . . . . . . . . . . . . . . . . . . . . 352-354, 365 Visible penetrants 81
air-coupled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371-372 Vision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 428-429
electromagnetic acoustic transducers (EMATs) . . . . . ... 373-374 blind spot . . . . . . . . . . . . . . . . . . . . . . . . . . . . 430
focused . . . . . . . . 390, 391-392 color . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 432-434
high frequency .......... .......... 372-373 peripheral . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 432
low frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371-372 texture/reflection and ......... . . . . . . . . . . . . 440
in straight beam testing . . . . . . . . . . . . . . . . . . . . . . . . 382, 388-389 Vision acuity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429-430
near field . . . . . . . . 389 vision acuity examinations 430-431, 432, 441
wheel transducers 409 Visual aids . . . . . . 440-448
Ultrasonic transducer shoes 400 Visual angle . . ........... .......... 432
INDEX I 581
Visual testing 425-472 applications . . . . . . . . . . . . . . . . . . . . . . . . . 188, 195-196
environmental factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 440-441 sensitivity 191-195
image enhancement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 447-448, 468 system components 191, 194
lighting. See Lighting X-ray diffraction mottling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
machine vision technology 468-471 X-ray equivalency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144-145
photographic techniques for . . . . . . . . . . . . . . . . . . . . . . . . . . . 446-447 X-ray exposure
remote positioning/transport systems . . . . . . . . . . . . . 465-467 exposure charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110, 159-161
safety aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 435-439 exposure factor . . . . . . . . . . 141-142
test object effects 441-443 See also Radiographic exposure devices
video technology application 457-464 X-ray fluorescence spectrometry . . . . . . . . . . .... 474
See also Optical testing X-ray generators . . . . . . . . . . . . . . . . . . . . 99
Volume computed tomography . . . . . . . . . . . . . . . . . . . . . . . . . . . 190 baseline information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Volume units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 circuits for 104, 105
V-path . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398, 405 control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108-109
high energy sources for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103-108
w kilovoltage adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108-109
maintenance 111
milliamperage adjustment .......... . . . . 109
operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110-113
Water, as ultrasonic testing couplant . . . . . . . . . . . . . . . . . . . 402, 407 safety aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112-113
See also Immersion ultrasonic testing sources for. See Radiographic isotope sources
Water cooled borescopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 452 unit selection . . . . . .............. 110-111
Water cooled eddy current probe transducer . . . . . . . . . . . . . . . 224 See also Radiography
Water jet devices, for immersion ultrasonic testing . . . . . . . . . . 409 X-ray image intensifiers . . . . . . . . . . . . . . . . . . . . . . . . . . 175-177, 181
Waterproof borescopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 452 X-ray nondestructive testing. See Radiography
Water soluble penetrant developers . . . . . . . . . . . . . . . . . . . . . . 82-83 X-radiography. See Radiography
Water suspendible penetrant developers . . . . . . . . . . . . . . . . . . . . .83 X-rays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92-93
Water washable penetrants 81, 84, 86 absorption 95-98, 144-145
Wedge shaped shoes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400 generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93-94
Welder's flash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 437 scattering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Welds X-ray safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
aircraft rotor wheels, immersion ultrasonic testing . . . . . . . . . . . . . . 415 X-ray sensitive vidicon cameras . . . . . . . . . . . . 182
angle beam contact ultrasonic testing of . . . . . . . . . . . 398-399, 404-406 X-ray surveys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
discontinuities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263 survey equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123-127
leak testing of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28-29, 50, 52-55 X-ray tubes................... ......... . 99-103
in pipes, remote field eddy current testing . . . . . . . . . . . . . . . . 208, 210 emission from . . . . . . . . . . . . ................. 133, 134
resistance spot welds, acoustic emission monitoring of . . . . . . . 322-330 microfocus, for radioscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
thermography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 494-495
Well casings
magnetic flux leakage testing . . . . . . . . . . . . . . . . . . . 242-243, 252-253 y
remote field eddy current testing . . . . . . . . . . . . . . . . . . . . . . . 206, 211
Willemite . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
Wet method magnetic particles 289, 290, 291
Wheel transducers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 409 Yield point . . . . . . . . . . . . . ........... . . . . . . . . . . . 477
Whittemore resistance strain gage . . . . . . . . . . . . . . . . . . . . 506 Yokedemagnetization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286
Wide field borescopes . . . . . . . . . . . . . . . . . . . . . . . . . 452 Yokes 277
Wide field macroscopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 446
Wide field tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 445-446
Wien's Displacement Law 481, 482
Wire penetrameters 166-169 z
Wire rope, magnetic flux leakage testing 242, 243, 251-252 Z (atomic number), dependence of photon absorption on ... 97-98
Zero liftoff impedance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
x Zirconium, radiation absorption by . . . . . . . . . . . . . . . . . . . . . . . . . 94
Zone lenses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 390-391
X-ray computed tomography 188-191
advantages/disadvantages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
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ASNT NDT Handbook Volume 10 OVERVIEW
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ASNT NDT Handbook Volume 10 OVERVIEW
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- 51 - 100
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- 251 - 300
- 301 - 350
- 351 - 400
- 401 - 450
- 451 - 500
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- 551 - 600
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