Plastic Deformation

· Thermal annealing of a cold-worked metal reduces the dislocation density, changes the configuration of dislocations and alters the grain size.
· Recovery processes driven by deformation induced internal stresses restore about 20 % of the original ductility of the un-strained material.
· Additional removal of the effects of cold- work come about by recrystallization. The diagram illustrates the effect of these processes on the tensile strength and ductility of a brass (70% Cu-30% Zn).

From: Callister,
"Materials Science & Engineering," Wiley (1994)