Hot forging and Cold forging

Hot forging is a metalworking process in which metals are plastically deformed above their recrystallization temperature, which allows the material to retain its deformed shape as it cools. ... However, tolerances used in hot forging are generally not as tight as in cold forging.The cold forging manufacturing process increases the strength of a metal through strain hardening at a room temperature. On the contrary the hot forging manufacturing process keeps materials from strain hardening at high temperature, which results in optimum yield strength, low hardness and high ductility.