Metal heat treatment processes can be roughly divided into three categories: overall heat treatment, surface heat treatment and chemical heat treatment. Depending on the heating medium, heating temperature and cooling method, each category can be divided into several different heat treatment processes. Using different heat treatment processes, the same metal can obtain different structures and thus have different properties.
Steel is the most widely used metal in industry, and the microstructure of steel is also the most complex, so there are many types of steel heat treatment processes. Overall heat treatment is a metal heat treatment process that heats the workpiece as a whole and then cools it at an appropriate speed to obtain the required metallographic structure to change its overall mechanical properties.
The overall heat treatment of steel generally includes four basic processes: annealing, normalizing, quenching and tempering.
