This document discusses various mechanical properties of materials: 1. Elasticity and plasticity refer to a material's ability to regain or not regain its original shape after a load is removed. 2. Other properties discussed include stiffness, ductility, brittleness, malleability, resilience, and toughness. 3. The stress-strain diagram is explained showing proportional limit, elastic limit, yield limit, ultimate point, and fracture point for ductile materials. Creep is also defined as deformation under continued loading at high temperatures.

1. Mechanical Properties

2. Material
Properties
1) Elasticity : It is the property
of the material by which it
can regain its original
shape & size when applied
load is removed.
1) Plasticity : The property
which enables the material
to regain its original shape
& size when applied load
is removed.

3. 3) Stiffness : Ability of the material to resist the deformation
under the load.
4 ) Ductility : Ability of the material to deform under the load
condition. measured in percentage of elongation or
reduction in cross section,

4. 5) Brittleness : Ability of the material to fail without the
deformation. Less than 5% elongation is considered
as a brittle material.
6) Malleability : property which allow material to deform without
rupture. it is considered when compressive load is applied.

5. Stress Strain
Diagram
Stress strain diagram for ductile material

6. • PROPORTIONAL LIMIT :
It is the maximum stress at which the stress is
proportional to strain and above this limit the plastic
deformation of a material occurs. That is nothing but the
hooks law. Which is given as,
stress / strain = a constant
• Here the constant is known as the Modulus of elasticity .

7. • Elastic limit : even if material is stressed beyond the
proportional limit , it can regain its original shape and
size. That is called elastic limit.
• Yield limit : it stress applied beyond elastic limit then
plastic deformation takes place. For ductile material
two yield point is obtained that is denoted by the
Y1&Y2.
• Ultimate point : maximum value of the stress which
is applied beyond the yield point .
• Fracture point : The value of the stress for which

8. 7) Resilience : Ability of the to absorb the
energy within elastic limit.
Modulus Of Resilience

9. 8) Toughness : Ability of the material to
absorb the energy without fracture.
Modulus Of Toughness

10. 9) Creep : The progressive deformation of the
material under continue and loading at a high
temperature.
Stress Vs Time Diagram For Creep test