2021 Volume 61 Issue 1 Pages 302-308
With the aid of a FEM software COMSOL Multiphysics the transient radiation heat transfer model has been established to simulate the vacuum heating process of M50NiL bearing rings. The heating curves obtained from the numerical model compare well with the experimental data. Based on the model, effects of heating process parameters on the radiative heat transfer in a vacuum furnace are investigated. The simulation results indicate that reducing heating rate or increasing preheating temperature can improve the temperature uniformity, thereby reducing the soaking time of bearing rings. Accordingly, an optimized heating process with high preheating temperature and low heating rate is proposed. The new process cuts the soaking time by a quarter and reduces the proportion of grade 3 and coarser grains from 12% to 2%.