Mechanical properties are properties that are associated with the ability of a metal to resist loads. They heavily influence the characteristics of a metal.

The following are some of the important mechanical properties of a metal:

Elasticity
Plasticity
Ductility
Toughness
Malleability
Strength
Stiffness
Creep
Resilience
Hardness

Elasticity:
Whenever an external force is applied on a metal, it deforms. Elasticity is the property by virtue of which a metal regains its original shape when the external force applied on it is removed.

Plasticity: Plasticity is the property by which a metal retains its deformation permanently, when the external force applied on it is removed.
Examples: forming, forging, hammering

Ductility: Ductility is the property by which a metal can be drawn into thin wires. It is determined by percentage elongation and percentage reduction in area of a metal.

Toughness: When a huge external force is applied on a metal, the metal will experience fracture. Toughness is the ability of a metal to resist fracture.

Malleability: It is the property by which a metal can be rolled into thin sheets. Highly malleable metals (like Mild Steel) are extensively used in making sheet metals.

Strength: When external forces are applied on a metal, breaking (brittle metal) or yielding (ductile metal) may occur. Strength is the property of a metal by which it resists external force without breaking or yielding.

Stiffness: When an external force is applied on a metal, it develops an internal resistance. The internal resistance developed per unit area is called stress. Stiffness is the ability of a metal to resist deformation under stress.

Creep: When a metal is subjected to a constant load (below its yield point), at high temperature, for a prolonged period of time, it undergoes a permanent deformation. This tendency of the metal is called creep.

Resilience: Resilience is the ability of a metal to absorb energy and resist soft and impact load.

Hardness: Hardness is the ability of a metal to resist permanent change of shape caused by an external force.