Knowledge of induction heat treatment equipment
Metal heat treatment process can be generally divided into three categories: integral 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.Different heat treatment processes can be used to
obtain different microstructure and properties of the same metal.Steel is the most widely used metal in industry, and the microstructure
of steel is the most complex, so the heat treatment process of steel is various.
Integral heat treatment is a metal heat treatment process in which the workpiece is heated as a whole and then cooled at an appropriate rate
to change its overall mechanical properties.The overall heat treatment of steel generally includes four basic processes: annealing, normalizing,
quenching and tempering.
Induction annealing is to heat the workpiece to the appropriate temperature, adopt different insulation time according to the material and workpiece size,
and then carry out slow cooling, the purpose is to make the internal structure of the metal to reach or close to the equilibrium state, to obtain good
process performance and use performance.
Normalizing is to heat the workpiece to an appropriate temperature and cool it in the air. The effect of normalizing is similar to annealing, except that
the obtained microstructure is more fine. It is often used to improve the cutting performance of materials, and it is also sometimes used as the final heat
treatment for some parts with low requirements.
Quenching is to heat the workpiece after heat preservation, in water, oil or other inorganic salt, organic water solution and other quenched medium cooling
quickly.After quenching, the steel becomes hard but brittle at the same time.In order to reduce the brittleness of steel pieces, the quenched steel pieces are
insulated for a long time at an appropriate temperature higher than room temperature and lower than 650℃, and then cooled. This process is called tempering.