kuumamuokkaukseen

Kuumamuokkaukseen, known in English as hot working or hot forming, refers to a metalworking process where a metal is shaped at a temperature above its recrystallization point. This means the metal is heated to a point where its internal structure can reform as it is deformed, preventing work hardening. The high temperature significantly reduces the metal's yield strength, making it much easier to deform.

Common methods of hot working include hot rolling, hot forging, hot extrusion, and hot drawing. Hot rolling is used to produce plates, sheets, and structural shapes. Hot forging shapes metal by hammering or pressing it into a die. Hot extrusion is used to create long, uniform shapes by pushing heated metal through a die. Hot drawing is similar to extrusion but involves pulling the metal through a die.

The primary advantage of hot working is that it allows for large deformations without fracturing the material and without inducing significant internal stresses. It also generally results in a finer grain structure, which can improve the mechanical properties of the finished product. However, hot working requires significant energy to heat the metal and can lead to surface oxidation, which may require subsequent cleaning or finishing operations. Furthermore, dimensional accuracy can be lower compared to cold working due to thermal contraction as the metal cools.