During the processing of metal accessories, according to the use function and use environment of the accessories, the surface of the metal accessories needs to be treated to meet the use standard.

Chemical surface heat treatment

1. Carburizing of steel: It refers to the process of infiltrating carbon atoms into the surface of steel. Improve the surface hardness, wear resistance, and fatigue strength of the workpiece, while maintaining the good toughness of the core; the carburizing steel is low carbon steel containing 0.1-0.25% C. The higher the carbon content, the lower the toughness of the core. Using vacuum carburizing treatment, the surface quality is good and the speed is fast; carburizing temperature: 900-950 ℃; carburizing layer thickness (thickness from the surface to half of the transition layer): - generally 0.5-2mm. Carburized layer surface carbon content: 0.85-1.05 is the best. The heat treatment after carburizing is quenching + low-temperature tempering, and the tempering temperature is 160-180 ℃.

2. Nitriding of steel: Nitriding refers to the process of infiltrating nitrogen atoms into the surface of steel. The nitridation temperature is 500-570°C; the thickness of the nitridation layer does not exceed 0.6-0.7mm. Characteristics and applications of nitriding: The surface hardness of nitride parts is high (69~72HRC), and the wear resistance is high. High fatigue strength. The workpiece deformation is small, and the corrosion resistance is good; it is used for parts with high wear resistance and precision requirements and heat-resistant, wear-resistant, and corrosion-resistant parts. Such as the small shaft of the instrument, the light load gear, and the important crankshaft.

The demand for metal market processing is increasing year by year, and more and more metal accessories need surface treatment because the precision, corrosion resistance, wear resistance, and strength of production and processing machinery and equipment require special treatment of metal accessories.