Editing Forging (section)

=== Forging of steel ===

Depending on the forming temperature steel forging can be divided into:<ref>Doege, E., Behrens, B.-A.: ''Handbuch Umformtechnik: Grundlagen, Technologien, Maschinen'' (in German), Springer Verlag, 2010, p. 7</ref>

* Hot forging of steel
** Forging temperatures above the recrystallization temperature between 950–1250&nbsp;°C
** Good formability
** Low forming forces
** Constant tensile strength of the workpieces
* Warm forging of steel
** Forging temperatures between 750–950&nbsp;°C
** Less or no scaling at the workpiece surface
** Narrower tolerances achievable than in hot forging
** Limited formability and higher forming forces than for hot forging
** Lower forming forces than in cold forming
* Cold forging of steel
** Forging temperatures at room conditions, self-heating up to 150&nbsp;°C due to the forming energy
** Narrowest tolerances achievable
** No scaling at workpiece surface
** Increase of strength and decrease of ductility due to strain hardening 
** Low formability and high forming forces are necessary

For industrial processes steel alloys are primarily forged in hot condition. Brass, bronze, copper, precious metals and their alloys are manufactured by cold forging processes; each metal requires a different forging temperature.