Analysis of heat treatment process of silicon steel sheet punching and punching die by high frequency heating equipment

Silicon steel sheet punching and punching film is a kind of cold working die commonly used in daily life. In the process of punching and punching, the cutting edge of punch and die needs to bear repeated huge shearing force, pressure, impact force and friction force. combined effect. Therefore, for a better processing effect, the punching die must have sufficient hardness and wear resistance, good impact toughness, sufficient fatigue strength, and dimensional stability. In terms of materials, high-carbon and high-alloy steel will be used for production. In terms of technology, high-frequency heating equipment is used to heat treat it, which not only improves the performance of silicon steel sheet punching and cutting film, but also prolongs its service life.

The mold is assembled from four pieces. In order to reduce the deformation of the mold and achieve high precision, each piece is heat treated separately, which is also convenient for processing and maintenance. It should be noted that during the heating process, the return When firing, special clamps should be used to clamp it for tempering treatment. Moreover, low-temperature tempering is used to eliminate the quenching stress of the blanking die. After two low-temperature temperings, the size of the die is stabilized without reducing its hardness and performance. It avoids the breakage of the silicon steel sheet punching and punching film during use.

At the beginning of the mold preheating treatment, the temperature of the high-frequency heating equipment should be lower than 600°C, and the mold should be fully deoxidized to avoid oxidation or decarburization of the surface of the punching die and reduce the temperature difference between the inside and outside. During quenching, the temperature will be higher and higher. We must adjust the temperature properly to avoid the decrease of mold hardness, reduce deformation or control its deformation. Finally, the mold will undergo a wire cutting process. Since the surface of the blanking die has residual stress, cracks will appear on the surface of the mold. For this, we will use high-frequency vibration to eliminate the residual stress, or the silicon steel sheet after quenching The punched and punched film is subjected to cold treatment, and then tempered again to avoid cracks and improve its strength, hardness, wear resistance and service life.