How does the rack manufacturer vacuum the rack surface?
The overall appearance of the rack is high strength, high hardness and high wear resistance. How can the rack achieve such performance? We know that when the rack is engaged, the outer layer is continuously worn due to mutual engagement, in order to effectively guarantee The working efficiency of the rack reduces the degree of wear and saves costs. The rack surface can usually be vacuum hardened.
The surface of the rack is quenched; the processed rack is first placed in the inductor coil, and when an alternating current of a frequency is not applied to the inductor, an alternating magnetic field is generated on all four sides. The sense current will be unevenly distributed on the cross section of the workpiece. The surface current density of the workpiece is high and gradually decreases inward. We call this symptom the “skin effect.”
At this time, the electric energy of the high-density current on the surface of the rack changes into heat energy, so that the temperature of the surface layer becomes high, and the surface temperature of the part rises rapidly. The higher the current frequency, the difference in current density attached to the surface of the workpiece and the inside. The higher the temperature, the thinner the heating layer. The rapid cooling after the temperature of the heating layer exceeds the critical point temperature of the steel completes the surface quenching of the rack.
After the rack is subjected to vacuum quenching and heat treatment, the surface of the tooth surface is higher than that of the heat-treated rack, and the wear resistance is strong, and the performance of the rack is improved as a whole.