Work hardening, also known as
strain hardening or
cold working, is the
strengthening of a metal by
plastic deformation. This strengthening occurs because of
dislocation movements and dislocation generation within the
crystal structure of the material. Many non-brittle metals with a reasonably high
melting point as well as several polymers can be strengthened in this fashion. Alloys not amenable to
heat treatment, including low-carbon
steel, are often work-hardened. Some materials cannot be work-hardened at low temperatures, such as
indium, however others can only be strengthened via work hardening, such as pure
copper and
aluminum.