Metal surface treatment is one of the main processing processes in mechanical equipment manufacturing. Compared with other manufacturing processes, heat treatment processes generally do not change the appearance and overall composition of product workpieces, but only grant or improve performance indicators of product workpieces based on changing the microscope mechanism inside the casting or changing the composition of the surface layer of the product workpieces. Its advantage is to improve the internal quality of product components, which is generally not visible to the eyes.

In order to achieve the required physical, technological, and chemical properties of metal material components, in addition to the effective use of materials and various forming and processing processes, heat treatment methods are usually indispensable. Steel is a widely used raw material in mechanical engineering. The arrangement of steel microscopes is complex and can be manipulated according to the heat treatment process. Therefore, the heat treatment process of steel is the specific content of metal surface treatment. In addition, aluminum, copper, magnesium, titanium and other aluminum alloys can also change their structural mechanics, physical and chemical properties according to the heat treatment process to obtain different performance indicators.

The heat treatment method generally includes three complete processes: heating, insulation, and refrigeration, and sometimes only two complete processes: heating and heat dissipation. This link is interconnected and cannot be interrupted. Heating is one of the main processes in heat treatment. There are many heating methods for metal surface treatment, using wood charcoal and coal as pyrogens, and using liquid and fossil fuels.

The use of electricity makes heating easy to control and free from air pollution. By using these pyrogens, simultaneous heating can be achieved, and molten salt or gold can also be used to indirectly heat up fluctuating objects. When metal materials are heated up, the product workpiece is exposed to the air, often resulting in air oxidation and carburization (i.e., the carbon composition on the surface of steel parts is reduced), which poses a significant threat to the appearance characteristics of the parts after heat treatment. Therefore, metal materials should generally be heated in a controlled or maintained atmosphere, such as molten salt and vacuum pumps, and can also be maintained and heated using building coatings or packaging methods. Heating temperature is one of the main processing parameters of heat treatment, and selecting and controlling the heating temperature is the primary challenge in ensuring the quality of heat treatment products.

The heating temperature varies depending on the metal material being solved and the significance of the heat treatment process, but generally it is all heated above the change in temperature to obtain a high-temperature mechanism. In addition, the change must take a certain amount of time, so when the surface layer of the metal material casting reaches the specified electric heating temperature, it must also be maintained at this temperature for a certain period of time to ensure that the internal and external temperatures are consistent and the microscope arrangement changes thoroughly. This period of time is called insulation and insulation time. When using high energy relative density heating and surface heat treatment processes, the heating rate is fast and generally there is no insulation time, while the insulation time of organic chemical heat treatment processes is usually longer.