Basic process of heat treatment of iron and steel

Integrated heat treatment of iron and steel, basic process of heat treatment

The whole heat treatment is a metal heat treatment process that heats the whole workpiece and cools it at a proper speed to change its whole mechanical properties. Changzhou heat treatment will tell you four basic processes of steel integral heat treatment.

Annealing → heating the workpiece to a proper temperature, adopting different holding time according to the material and workpiece size, and then cooling slowly (cooling speed is slow), so as to make the internal structure of the metal reach or close to the equilibrium state, obtain good process performance and use performance, or make organization preparation for further quenching.

Normalizing → heating the workpiece to a suitable temperature and cooling it in the air. The effect of normalizing is similar to that of annealing, but the microstructure obtained is finer, which is often used to improve the cutting performance of materials, and sometimes used for the final heat treatment of some parts with low requirements.

Quenching → after the workpiece is heated and insulated, it is cooled rapidly in water, oil or other inorganic salt, organic water solution and other quenching media. After quenching, the steel becomes hard but brittle at the same time. In order to reduce the brittleness of steel parts, the quenched steel parts are kept warm for a long time at a proper temperature higher than room temperature but lower than 710 ℃, and then cooled. This process is called tempering. Annealing, normalizing, quenching and tempering are the "four fires" in the whole heat treatment, in which quenching and tempering are closely related and often used together.

With the different heating temperature and cooling mode, the "four fire" evolved different heat.