EM025 CHAPTER 1 ENGINEERING MATERIAL

M AT R I C U L AT I O N ENGINEERING
MATERIAL

KEJURUTERAAN MEKANIKAL EM025

1.1 CLASSIFICATION OF MATERIALS

LEARNING OUTCOMES

a) Differentiate the various types of materials used i) Define alloy metal.
in engineering:
j) State the characteristic, mechanical properties
▪ Metal, ceramics and polymers. and applications of:
▪ Brass, bronze, pewter, stainless steel and
b) Define ferrous metal.
duralumin.
c) Explain types of ferrous metal:
▪ Steel and iron. k) Define advance materials.

d) Distinguish classification of steel: l) State the characteristic, mechanical properties
▪ Carbon steel and alloy steel. and applications of:
▪ Piezoelectric, smart fluids, choromogenic
e) Distinguish classification of iron: and ferrofluids.
▪ Cast iron and wrought iron.

f) Define non-ferrous metal.

g) Describe the general characteristics of non-
ferrous metal.

h) State the characteristic, mechanical properties
and applications of:

▪ Aluminium, zinc, copper and tin.

INTRODUCTION

• In modern society we are surrounded by an amazing variety of materials. Most of the
materials have been modified to make them more suitable for practical applications.

• In the 1960's plastics were used to make colorful toys and housewares at such a low cost
that they were frequently disposed of and replaced with the latest style. In the 1980's
silicon based electronics started spreading through businesses and homes. In the 21st
century, materials definitely follow a global cycle. Raw materials are collected; processed
into useful materials; sold to consumers; and eventually discarded as waste.

• Many engineers will at one time be exposed to a design problem involve selecting the
right material from the many thousands that are available.

• There are several criteria on which the final decision is normally based such as :
i. The physical, mechanical and chemical properties of the material.
ii. Deterioration of material that may occur during service operation.
iii. Consideration of economics.

Traditionally three major classes of materials are metals, polymers, and ceramics. Examples of these are steel,
cloth, and pottery. These classes usually have quite different sources, characteristics, and applications

METAL CERAMICS POLYMERS

DEFINITION Metals are solid substances and Produced by high temperature A long molecule consisting of a
chain many repeating units.
have an excellent electric firing of inorganic, nonmetallic
High strength to weight ratios,
conductance. rocks and minerals. toughness, resilience,
resistance to corrosion, lack of
PROPERTIES Metals have the property of Ceramic materials are brittle conductivity (heat and electric).
ductility and malleability. and hard.

EXAMPLE

FERROUS METAL

• Ferrous metals are metal with iron element as the base metal.
• Examples of ferrous metal are iron and steel.

DURABLE GREAT RECYCLABLE
TENSILE
These qualities make them usable in STRENGTH USUALLY
building constructions as well as in MAGNETIC
GENERAL
making tools, vehicle engines, PROPERTIES
pipelines, containers, automobiles,
GOOD
cutlery etc. CONDUCTORS

LOW OF
RESISTANCE ELECTRICITY

TO
CORROSION

FERROUS METAL

STEEL IRON

CARBON STEEL ALLOY STEEL CAST WROUGHT
LOW LOW

MEDIUM HIGH
HIGH

FERROUS METAL

IRON STEEL

➢ Basic constituent of steel. ➢Steel is defined as the
➢ Most rich metallic in the element of iron and
carbon.
earth’s crust after aluminum.
➢ Found in the form of ores as ➢Steel are supplied in
various forms such as
oxides, carbonates, silicates plates and wires to
and sulfides. suit its applications. Its
➢ Produced in blast furnaces. usage depends on the
➢ Carbon exerts the most percentage of carbon
significant effects on the in its composition.
microstructure and
properties of iron products.

STEEL

CARBON STEEL ALLOY STEEL

• Carbon steel can be classified into three • Alloy steel is steel that is alloyed with a
types: variety of elements in total amounts
Low Carbon Steel between 0.1% and 50% by weight to
(0.15% - 0.30% Carbon) improve its mechanical properties.
Low hardness, ductile and easy to shape.
• Additional of alloying elements will altered
Medium Carbon Steel the mechanical properties of steel like
(0.30% - 0.80% Carbon) hardenability, brittleness, toughness,
Strong and tougher than low carbon stiffness, machinability and ductility.
steel.
• Low Alloy Steels is to increase strength and
High Carbon Steel hardenability. Product : Mild steel.
(0.8% - 1.5% Carbon)
Hardness, toughness, durability and • High Alloy Steels is to improves corrosion
brittle. resistance and stability at high or low temps.
Product : Stainless steel.

CARBON STEEL ALLOY STEEL

USED TO MAKE USED IN
LATHE TOOL BITS,
PIPELINES,
RIVETS, AUTO PARTS,
ROD, TRANSFORMERS,
POWER GENERATORS
SPRING, ELECTRIC MOTORS.
CHISEL,
WRENCH,
HAMMER

IRON

CAST IRON WROUGHT IRON

• Manufactured by reheating pig iron as liquid • Made by repeatedly heating the iron and
metal casts into a prepared mold. working it with tools to deform it such as
forging, knocking, squeezing and rolling.
• Group of iron-carbon alloys with a carbon
content greater than 2%. • An iron alloy with a very
low carbon content (less than 0.08%).
• Its usefulness derives from its relatively low
melting temperature. • Strong in tension and weak in
compression.
• Properties: High compressive strength, low
tensile strengths, tends to be brittle, except • Properties: Ductile and malleable, tough
for malleable cast irons. and has great shock resistance.

WROUGHT CAST IRON
IRON
USED IN
USED TO MAKE
PIPES PIPES
MACHINES
CORRUGATED AUTOMOTIVE INDUSTRY
SHEETS PARTS SUCH AS
GRILLS -CYLINDER HEADS
BARS -CYLINDER BLOCKS
CHAINS -GEARBOX CASES
GATES

NON- FERROUS METAL

• Ferrous metals are metal without iron element .
• Examples of ferrous metal are aluminium, zinc, copper and tin.

CORROSION
RESISTANCE

COLORS CHOICES GENERAL HIGH THERMAL
PROPERTIES AND ELECTRICAL
CONDUCTIVITY

These qualities make them usable in in a EASE OF
wide range of applications, including FABRICATION

electrical circuits and wiring, aerospace
components, jewelry, and automobile parts.

NON FERROUS METAL

ALUMINIUM COPPER

ZINC TIN

Characteristics

A ➢ Silver in color.
L ➢ It is a good heat and electrical conductor.

➢ Low melting point

U ➢ Non-poisonous
M Mechanical Properties
I ➢ Ductile

➢ Malleable Low density

NI ➢ High heat capacity
U Application

➢ Used in transportation vehicles, construction industry,

M aeronautics, cooking utensils and food containers .

APPLICATION OF ALUMINIUM

Vehicles

Cooking utensils

Food containers

Construction

Characteristics
➢ Blue-white in color
➢ Hard, smooth material
➢ Reasonable conductor of electricity

Z ➢ Does not corrode as easily as other metals
I Mechanical Properties
N ➢ Brittle at ambient temperatures

➢ Malleable at 100 to 150°C

C
Application
➢ Used for die-casting alloys and as a coating for sheet

steel, chain, wire, screws and piping.
➢ Used in die-casting industries to produce automotive

parts, building hardware, padlock and toys.

APPLICATION OF ZINC

Coating for chain Padlocks

Plated screws Building hardware Coating for piping
Toys

Characteristics
➢ Reddish-colored metal
➢ It is a good heat and electrical conductor.

C ➢ Can be easily soldered, brazed and welded
O without corrosion problems.
P Mechanical Properties

➢ Malleable

P ➢ Ductile
E ➢ Tough
R Application

➢ Widely used in electrical and air-conditioning

industries

APPLICATION OF COPPER

Electronics product Copper plating

Copper finish parts Copper wires

Characteristics
➢ Silvery-white in color.
➢ Low melting point
➢ Good transmission of heat or electricity

T ➢ Being so soft, tin is rarely used as a pure metal
➢ Can be forged and hammered to fine sheet and wires.

I Mechanical Properties
N ➢ Malleable (easy to press and shape without breaking)

➢ Ductile (able to be stretched without tearing).

A➢ppUlisceatfioornelectronic connections; soldering
➢ used to coat other metals to prevent corrosion
➢ used in food containers industry and pewter industry

APPLICATION OF TIN

Soldering Pewter industry

ALLOY METAL

• An alloy is an admixture of metals, or a metal combined with one or more other elements.

• In general, alloys have been found to be stronger and harder, less malleable, less ductile, and
more corrosion-resistant than the main metal making the alloy.

• An alloy mixture is stronger because it contains atoms from different elements that are
different in sizes.

• For example, combining the metallic elements gold and copper produces red gold, gold and
silver becomes white gold, and silver combined with copper produces sterling silver.

• Combining iron with non-metallic carbon or silicon produces alloys called steel or silicon
steel.

ALLOY METAL

BRASS PEWTER DURALUMIN

BRONZE STAINLESS STEEL

DEFINITION PROPERTIES APPLICATIONS

• Brass is an alloy made • Strength, machinability, • Used in applications
primarily of copper and ductility, wear- where corrosion
zinc. resistance, hardness, resistance and low
electrical and thermal friction are required,
• Often a bright gold , conductivity, hygiene such as locks, gears,
however, it can also be and corrosion bearings, plumbing, and
reddish-gold or silvery- resistance. electrical plugs and
white. A higher sockets.
percentage of copper
yields a rosy tone, while • Also use in musical
more zinc makes the instruments,
alloy appear silver. decoration, tools and
fittings used around
explosives.

DEFINITION PROPERTIES APPLICATIONS

• Consisting primarily of • Hardness and brittleness • Use in boat and ship
copper, commonly with (although typically it is fittings prior to the wide
tin and with the addition less brittle than cast employment of stainless
of other metals. iron) steel owing to its
combination of
• Often a reddish-brown • Melting point of 950 toughness and
colour. degrees Celsius. resistance to salt water
corrosion.
• High resistance to
corrosion from saltwater. • widely used for springs,
bearings, bushings,
• Exhibits low metal-to- automobile transmission
metal friction. pilot bearings, and
similar fittings, and small
electric motors.

DEFINITION PROPERTIES APPLICATIONS

• Consisting of tin, • Known for its • Used to manufacture
antimony, copper, malleability and serving dishes for cold
bismuth, and ductility. This means food, dishes, cups and
sometimes silver. pewter is easily bent or tankards, candlesticks,
hammered into other knickknacks, buttons
• Often a bluish white shapes without and art pieces. It is a
with either a crisp, breaking, splitting or good metal for jewelry
bright finish or a soft, cracking. making.
satin sheen.
• Low melting point.

DEFINITION PROPERTIES APPLICATIONS

• Steel is an alloy of iron • Corrosion resistant • Used to:
and carbon. Stainless • High tensile strength • Automotive and
steels are steels • Very durable
containing chromium, • Temperature resistant transportation
and other alloying • Easy formability and • Medical technology
elements. • Building trade
fabrication • Aircraft construction.
• By controlling the • Low-maintenance (long
thickness of the oxide
layer, can obtain colors lasting)
that vary from bronze • Attractive appearance
to blue, gold, purple • Environmentally
and green
friendly (recyclable)

DEFINITION PROPERTIES APPLICATIONS

• An alloy of aluminum, • Corrosion resistant • Making screw machine
copper, magnesium, products.
and manganese. • It is a malleable metal
and can be easily • Aircraft fittings, space
• Often a white grey shaped. booster tankage and
colour. truck frame, and other
• It is a very good suspension
conductor of heat and components.
electricity.
• Aircraft structures,
• Strong, light-weighted, truck wheels, screw
and hard alloy of machine products,
aluminum. rivets, and other
structural application
• Soft, ductile, and products.
workable when they are
in a normal state.

ADVANCE MATERIALS

• Materials that are specifically engineered to exhibit novel or enhanced
properties that confer superior performance relative to conventional
materials.

• Also known as materials with engineered properties created through
the development of specialized processing and synthesis technology,
including ceramics, high value-added metals, electronic materials,
composites, polymers, and biomaterials.

• Meaning: Involving electric polarization resulting from the application of
mechanical stress.

• Characteristics: Piezoelectric materials exhibit both a direct and a reverse
piezoelectric effect. The direct effect produces an electrical charge when a
mechanical vibration or shock is applied to the material, while the reverse effect
creates a mechanical vibration or shock when electricity is applied.

• Properties: Piezoelectric property is due to atomic scale polarization. In theory,
piezoelectricity refers to a reverse process in which a contraction or elongation is
created in the crystal once it is positioned in an electric field. Crystals can only be
piezoelectric if they are non-centrally symmetric.

Applications: Being use in many useful
applications, including the production
and detection of sound, piezoelectric
inkjet printing, generation of high voltage
electricity, as a clock generator in
electronic devices. It is used in the
pickups of some electronically amplified
guitars and as triggers in most modern
electronic drums. Also finds everyday
uses, such as generating sparks to ignite
gas cooking and heating devices,
torches, and cigarette lighters.

• Meaning: A smart fluid is a fluid whose properties can be changed by applying an
electric field or a magnetic field.

• Characteristics: Smart fluids belong to the class of field responsive composites
and they have the capacity to undergo significant, reversible and controllable
transformations with respect to their material characteristics.

• Properties: These materials have the ability to change from a liquid to a solid
almost instantly when subjected to electric or magnetic field. Smart fluid
comprises a suspension of micro-meter-sized particles in a dielectric carrier liquid

• Applications: Smart fluids, which
change some of their material
properties when subjected to an
electric or magnetic field, are used
for damping, vibration reduction
and shock absorption in a variety
of applications.

• Meaning: Colorless, endogenous or exogenous pigment precursors that may
be transformed by biological mechanisms into colored compounds; used in
biochemical assays and in diagnosis as indicators, especially in the form of
enzyme substrates.

• Characteristics: These technologies consist of electrically-driven media
including electrochromism, suspended particle electrophoresis, polymer
dispersed liquid crystals, electrically heated thermotropics, and gaschromics.

• Properties: It is dynamic and interactive in nature. So that, it commonly used
when referring to the study and use of materials that show a reversible change
in their optical properties when they are subjected to certain ambient
conditions and different external stimuli, such as light, electric field.

• Applications: In chromogenic
photography, film or paper
contains one or many layers of
silver halide emulsion, along
with dye couplers that, in
combination with processing
chemistry, form visible dyes.
Also can be used for large area
glazing in buildings,
automobiles, planes, and for
certain types of electronic
display.

• Meaning: A liquid that is attracted to the poles of a magnet. It is a colloidal liquid
made of nanoscale ferromagnetic, or ferrimagnetic, particles suspended in a
carrier fluid.

• Characteristics: Each magnetic particle is thoroughly coated with a surfactant to
inhibit clumping. Large ferromagnetic particles can be ripped out of the
homogeneous colloidal mixture, forming a separate clump of magnetic dust when
exposed to strong magnetic fields.

• Properties: Composed of three components: magnetic nano particles, dispersion
medium (also called carrier liquid) and a dispersant or surface active agent. The
fluid responds to an applied magnetic field as one homogeneous system.

• Applications: Used to form liquid seals
around the spinning drive shafts in hard
disks. The rotating shaft is surrounded by
magnets. A small amount of ferrofluid,
placed in the gap between the magnet
and the shaft, will be held in place by its
attraction to the magnet. The fluid of
magnetic particles forms a barrier which
prevents debris from entering the interior
of the hard drive.

1.2 MATERIALS STRUCTURE

LEARNING OUTCOMES

a) Describe different types of bonding energy such as ionic, covalent and metallic
b) Describe material structure configurations for face centered cubic (FCC) and body

centered cubic (BCC).

INTRODUCTION

• A chemical bond is a lasting attraction between atoms, ions or
molecules that enables the formation of chemical compounds.

• The bond may result from the electrostatic force of attraction
between oppositely charged ions as in ionic bonds or through
the sharing of electrons as in covalent bonds.

• Bonds can be divided into two broad categories; primary bonds
and secondary bonds.

• Primary bonds are the chemical bonds that hold atoms in
molecules, whereas secondary bonds are the forces that hold
molecules together.

• There are three types of primary bonds namely ionic bonds,
covalent bonds, and metallic bonds.

• Secondary bonds include dispersion bonds, dipole bonds, and
hydrogen bonds.

• Primary bonds have relatively high bond energies and are more
stable when compared with secondary forces.

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IONIC

PRIMARY COVALENT
SECONDARY
TYPES OF METALLIC
CHEMICAL
BONDING DISPERSION
BONDS

DIPOLE BONDS

HYDROGEN
BONDS

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