Abstract: Comsol software was used to simulate the induction tempering of 30CrMnSiNi2A steel. The effects of power frequency, current, and structure and size parameter of coil on temperature homogenity in the workpiece during induction heating were studied by using control variable method. The results show that the greater the current intensity and power frequency, the greater the heating rate of the workpiece in the induction heating process, the higher the final balance temperature, but the greater the radial/axial temperature difference. The more turns of the coil, the greater heating rate and radial/axial temperature difference of the workpiece, as well as the higher the final balance temperature. The change of coil radius will only affect the heating rate at the end of the workpiece, the smaller the coil radius, the faster the heating rate at the end of the workpiece, and the smaller the axial temperature difference. The change of coil section outer diameter and wall thickness has no effect on the temperature field of the workpiece during induction heating. According to the comparative analysis of the simulation results, a method of combining sectional heating method with adding magnetic flux concentrator is proposed to optimize the induction tempering system. Through design optimization, it is possible to eliminate the radial temperature difference of the workpiece during induction heating, while also controlls the axial temperature difference to be within 10 ℃.

Key words: 30CrMnSiNi2A steel, induction heat treatment, numerical simulation, power parameters, coil structure, temperature field