Hardening (metallurgy)

Hardening is a metallurgical metalworking process used to increase the hardness of a metal. The hardness of a metal is directly proportional to the uniaxial yield stress at the location of the imposed strain. A harder metal will have a higher resistance to plastic deformation than a less hard metal.

The five hardening processes are:

All hardening mechanisms introduce crystal lattice defects that act as barriers to dislocation slip.

Material hardening is required for many applications:

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