MATERIAL SCIENCE

1. Mechanical Properties Of Materials
BY
Dr. K. SENTHILARASAN
ASSISTANT PROFESSOR
DEPARTMENT OF PHYSICS
E.G.S.PILLAY ARTS & SCIENCE COLLEGE
NAGAPATTINAM-611002

2. • Elasticity:
Elasticity is defined as the tendency of a body by virtue
of which it suffers a change in shape or size under the action of
external deforming forces or loads and regains its original
shape or size after the removal of the deforming.
• Plasticity:
Plasticity is defined as the property of a material by
virtue of which a permanent deformation takes place,
whenever it is subjected to the action of external deforming
forces or load.
Thus after the elastic limit, if the load is increased the
material is no longer capable of regaining its original shape or
size and a permanent set or permanent deformation force.

3. • Ductility:
Ductility is the property of a material by
virtue of which it can undergo considerable plastic
deformation before rupture.
A ductile material can be drawn into a wire or
considerably elongated before rupture take places.
• Brittleness:
Brittleness is the property of a material by
virtue of which it will fracture without any
appreciable deformation.
Thus, it is the opposite of ductility.

4. • Hardness:
Hardness is the property of a material by
virtue of which it is able to resist abrasion,
indentation, deformation and scratching.
• Toughness:
Toughness is the property of material by
virtue of which it can be absorb maximum
energy before fracture take place.

5. • Stiffness:
Stiffness is the property of a material by virtue
of which it resists deformation.
Modulus of elasticity is a measure of stiffness
of a metal.
• Resilience:
Resilience is the property of a material by
virtue of which it stores energy and resists shocks or
impacts.
Resilience is the important property to be
considered when we select materials for making
springs.

6. • Endurance:
The endurance is the property of a material by
virtue of which it can be withstand varying stresses or
repeated application of stress.
It is the important property in the design and
production parts in a reciprocating machines and
components subjected to vibrations.
• Strength:
Strength is the property of a material by virtue of
which it resists or with stand the application of an external
force or load without rupture.
A metal has different types of strengths.
Depending upon the value of stress, the strength of a
metal may be tensile, compressive, shear, bending and
torsional.

7. THANK YOU