Grinding Balls cooling is also an indispensable step in the heat treatment process, the cooling method varies with the process, the main is to control the cooling rate. General annealing the slowest cooling, normalizing cooling faster quenching cooling faster. However, there are also different requirements for the type of Grinding Balls steel. For example, the bare hard steel can be hardened with the normal cooling rate.
Grinding Balls heat treatment process can be broadly divided into overall heat treatment, surface heat treatment and chemical heat treatment three categories. Depending on the heating medium, the heating temperature and the cooling method, each major category can be distinguished as several different heat treatment processes. The same kind of Grinding Balls uses different heat treatment processes to get different tissues and thus different properties. Steel is the most widely used metal in the industry, and its microstructure is also the most complex, resulting in a wide range of steel heat treatment processes.
The overall heat treatment is the Grinding Balls heat treatment process that heats the entire workpiece and then cools it at an appropriate rate to change its overall mechanical properties. The overall heat treatment of steel generally have annealing, normalizing, quenching and tempering four basic processes.
Annealing is the heating of the workpiece to the appropriate temperature, according to the size of the material and the workpiece with different holding time, and then slow cooling, the purpose is to make Grinding Balls internal organization at or near equilibrium, access to good process performance and performance, or to further Quenching for organizational preparation. Grinding Balls Normalizing the workpiece is heated to a suitable temperature in the air after cooling, the effect of normalizing with annealing similar, but the resulting tissue finer, commonly used to improve the material's cutting performance, and sometimes used for some less demanding Parts as the final heat treatment.
Grinding Balls quenching is the workpiece after heating and insulation, in water, oil or other inorganic salts, organic aqueous quenching medium rapid cooling. After quenching the steel hardens, but at the same time becomes brittle. 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 650 ° C, and then cooled. This process is called tempering. Annealing, normalizing, quenching, tempering is the overall heat treatment in the "four fire", of which quenching and tempering are closely related, often with the use of indispensable.