High-frequency heat treatment process for stainless steel kitchen knives quenched by high-frequency quenching equipment

The material of stainless steel kitchen knife is 3Cr13 or 4Cr13, and the external dimension is 180mmX80mmX2.5mm. After rough grinding to 0.8-0.9mm, the cutting edge is subjected to induction quenching heat treatment in a high-frequency quenching furnace. After quenching, it meets the following requirements: hardness 50-56HRC, hardened area ≥25mm, uniform hardness distribution, and deformation ≤2mm.

1) Electrical parameters of the device. The input voltage is 380V, the anode voltage is 7.5kV, the anode current is 2.5A, the tank voltage is 5kV, the grid current is 0.6A, and the frequency is 250kHz.

2) Quenching heating process. High-frequency quenching furnace is used for quenching. A special inductor should be designed. The kitchen knife should be placed in a suitable position in the inductor. The induction heating speed is generally 200-400℃/s. Austenitization is completed in an instant, and no heat preservation is required. . The quenching heating temperature is 1050-1100℃, and the coolant is oil. Temper at 200-220℃.

Within the range of 180mm X25mm in the hardened area, the hardness after quenching and tempering is all >50HRC, and the hardness is relatively uniform. All indicators can meet the technical requirements.