What is the process called that strengthens metal through cold working?

The process that strengthens metal through cold working is known as work hardening. This occurs when a metal is subjected to deformation at temperatures lower than its recrystallization temperature, leading to an increase in dislocation density within the metal's crystal structure. As a result, the metal becomes harder and more resistant to further deformation. This characteristic is essential in various manufacturing processes where improved strength and durability are desired without requiring high-temperature treatments.

Annealing refers to a heat treatment process that softens metal, reducing hardness and improving ductility. Hardening, while it may sound similar, typically involves heating a metal to a high temperature followed by rapid cooling, which alters its microstructure to increase hardness. Tempering is often a subsequent process used after hardening, where the metal is reheated to a lower temperature to reduce brittleness while maintaining some level of hardness. Each of these processes has its specific applications and effects, distinguishing them from work hardening, which focuses solely on strengthening through cold deformation.