Introduction to Engineering Material

1. BASIC MECHANICAL
BASIC MECHANICAL
ENGINEERING
ENGINEERING
BT 203
BT 203
INTRODUCTION
to
ENGINEERING MATERIALS

2. INTRDUCTION :
INTRDUCTION :
ENGINEERING MATERIALS
ENGINEERING MATERIALS
 The knowledge of Engineering Material is
very vital for their effective use in the
very vital for their effective use in the
manufacturing of products.

3. TYPES OF ENGINEERING
TYPES OF ENGINEERING
MATERIALS:
MATERIALS:
MATERIALS
METAL NON METAL
METAL NON METAL
FERROUS NON
FERROUS
PLASTIC
ELASTOMER
CERAMICS
COMPOSITES

4. Properties of Metal
Properties of Metal
 Good machinibility and ductility.
 Good electrical and thermal conductivity.
 Form alloys.
 Available in solid form in room
 Available in solid form in room
temperature.
 Shinning appearance.

5. FERROUS METAL
FERROUS METAL
 The material which consists of large
percentage of iron (Fe) are classified as
Ferrous Metal
IRON ORE IRON
PIG IRON
IS PRODUCED
FROM IRON
OXIDE in
PRESENCE OF
IRON ORE
(IRON
OXIDE)
IRON
EXTRACTED
IN
FURNACE
PRESENCE OF
COKE in
FURNACE,
COKE ACTS
AS REDUCING
AGENT
PIG IRON
IS FORMED
PIG IRON
Composition
Iron (Fe),
Carbon: 3 – 4.5 %,
Manganese : 0.10-2.5%,
Silicon: 1 – 3 %,
Sulphur: 0.05 – 0.1%,
Phosphorus: 0.1 – 2 %

6. Non Ferrous Metal
Non Ferrous Metal
 Materials which do not contain Iron (Fe)
or posses very small percentage of Iron,
are classified as Non- Ferrous Metals.
 Examples :
Aluminum, Copper, Nickel, Titanium, Zinc,
etc.

7. Non Metal
Non Metal
Examples of Non- Metal:
 Wood
 Ceramics
 Composites
 Polymers/Plastics
 Available in solid, liquid, gaseous form.
 Do not form Alloy.
 Poor Electrical and Thermal conductivity.
Properties of Non Metal
Properties of Non Metal
 Polymers/Plastics

8. Ceramics
Ceramics
 The term “Ceramics” is taken from the greek word “ fired
material”
 Example of Ceramic material:
 Porcelain
 Glass
 Cement
 Cement
 Brick
 Earthenware
 Refractories
 Abrasives
Ceramics Consists of Metals and Non- Metals bonded
together chemically.
Applications: Furnace linings, etc.

9. Composites
Composites
 A composite material is composed of two
or more materials bonded together in
which one material serves as a matrix
surrounding the particles (or fibers) of the
other materials.
other materials.
Properties of Composites:
•High Strength
•Good Toughness
•High Stiffness
•Light in Weight
•Excellent resistance to corrosion.

10. Properties of materials
Properties of materials
Physical Properties
Physical Properties Chemical Properties
Chemical Properties
•
•Mechanical
Mechanical properties
properties
•
•Thermal properties
Thermal properties
•
•Electrical
Electrical properties
properties
•
•Magnetic Properties
Magnetic Properties
•
•Optical properties.
Optical properties.

11. Mechanical Properties of Metal
Mechanical Properties of Metal
 The mechanical properties of a material or metal are
determined while it is subjected to applied Force or
Pressure.
 Components are subjected to two types of loading , i.e.
Static and Dynamic.
Mechanical Properties
Mechanical Properties
Mechanical Properties
Mechanical Properties
STATIC
PROPERTIES
DYNAMIC
PROPERTIES

12. Static Properties
Static Properties
 Modulus of elasticity
 Yield strength
 Ultimate Tensile strength
Percentage Elongation
Static properties of material are determined under Static
loading:

 Percentage Elongation
 Percentage Reduction in Area
 Ductility
 Brittleness
 Toughness
 Hardness

13. Dynamic Properties
Dynamic Properties
 Fatigue limit
 Creep
 Impact strength
In real life components are subjected to dynamic loading: a.
Sudden Loads, b. Repeated loads, c. Fluctuating loads
 Impact strength

14. Common
Common Mechanical
Mechanical Properties:
Properties:
 Strength
 Hardness
 Brittleness
 Toughness
 Ductility
 Malleability
 Malleability
 Elasticity
 Plasticity
 Stiffness
 Resilience
 Stress
 Strain

15. Strength
Strength
o Strength is defined as the capacity of
the material to sustain load or force.
o The nature of forces that generally act
on a machine component may be tensile,
on a machine component may be tensile,
compressive or shear.
o Therefore the strength is also termed as
Tensile Strength, Compressive Strength,
Shear strength.

16. H
Hardness
ardness
o Hardness is a measure of the
resistance of a material to
permanent deformation (or abration
or indentation)

17. Brittleness
Brittleness
o Brittleness is defined as the tendency
of a material to fracture when subjected
to shocking load.
o Material having less than 5%
o Material having less than 5%
elongation can be considered as Brittle.

18. Toughness
Toughness
oToughness is defined as the ability of a
material to resist fracture under shock
loading when loading has crossed elastic
limit.

19. Ductility
Ductility
oDuctility is defined as the ability of
material to be drawn into wire.
o Ductility can be measured by
determining the percentage elongation.
o Material having 15% or more
o Material having 15% or more
percentage elongation can be
considered as Ductile material.

20. Malleability
Malleability
oMalleability is defined as the ability of
material to withstand the deformation in
all direction without cracking when load
is applied.
o The property of malleability is
o The property of malleability is
considered when forming of material
into sheets.

21. Elasticity
Elasticity
o Elasticity is defined as the property of
the material to return to its initial shape
and size after the removal of Force.

22. Stiffness
Stiffness
o Stiffness is defined as the property of
the material which enables to deform
deformation.

23. Plasticity
Plasticity
oPlasticity is defined as the ability to be
be deformed permanently without
fracture by application of Force after the
force is removed.

24. Resilience
Resilience
o Resilence is defined as the ability of a
material to store energy and to resist
shock and impact.

25. Stress
Stress
oStress is the internal resistance offered
by the material under application of
force (load).
o Stress = Load/ Unit Area
o Stress = Load/ Unit Area
o Stress, σ = F/ Ao
oUnit of Stress: Newton/ m²

26. Strain
Strain
oStain is defined as Change in length to
the original length of the specimen
under Load.
oStrain = (Lf – Lo) / Lo = Δ L / Lo
oStrain = (Lf – Lo) / Lo = Δ L / Lo