Fatigue: Fatigue phenomena occur when a material is subjected to cyclic loading, causing damage, which may progress to failure.
Endurance limit: Endurance limit is the magnitude of stress below which material has a high probability of not failing under reversals of stress.
• For a large number of steels, there is a direct correlation between tensile strength and fatigue strength, higher tensile strength steels have higher endurance limits. The endurance limit is normally in the range of 0.35 to 0.60 of the tensile strength.
Creep: Creep is the tendency of materials to deform when subjected to long-term stress, particularly when exposed to heat.
Plasticity: Plasticity is the characteristic of the material by which it undergoes inelastic strain beyond those at the elastic limit.
• The Property of plasticity is useful in operation of pressing and forging.