There are four basic processes for steel heat treatment: normalizing, quenching, and tempering.

Normalizing: normalizing, also known as normalizing. The workpiece is heated to the appropriate temperature after cooling in the air, the effect of normalizing is similar to annealing, but the obtained organization is finer, often used to improve the cutting performance of the material, and sometimes used for some parts with low requirements as the final heat treatment.

Quenching: heat treatment process in which the workpiece is heated to austenitic and then cooled in an appropriate manner to obtain martensite or bainite structure. The most common are water-cooled quenching, oil-cooled quenching, air-cooled quenching and so on.

Tempering: in order to reduce the brittleness of the steel, the quenched steel is insulated for a long time at an appropriate temperature higher than room temperature and lower than 710° C, and then cooled, this process is called tempering.