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. The ability of a material to resist fracture due to high impact loads, is called toughness.

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.

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.