Effect of Non-uniform Cooling on Distortion and Ellipticity in Bearing Quenching

Abstract

The bearing outer ring is often non-uniformly deformed after quenching. The ellipticity of the bearing is also an evaluation indicator for quality control. In this paper, the cooling curves of the inner and outer surfaces of the bearing outer ring were measured separately. Based on the measured cooling curves, the cooling rates were calculated, and the heat transfer coefficients at the measurement points on the inner and outer walls of the bearing outer ring were calculated using the inverse analysis method. The heat transfer coefficients at measurement points on the inner and outer walls of the bearing ring were calculated under different quenching postures, revealing the non-uniform heat transfer mechanism during the bearing quenching process. Through experiments, thermal physical properties such as the phase transformation plasticity coefficient of GCr15 material were measured., the quenching processes of GCr15 materials, were simulated according to the metal thermodynamics theory and the multi-field coupling calculation method. Through the simulation, the results of distortion of the bearing sleeve after quenching were obtained, and the ellipticity values of the bearing sleeve after quenching were obtained according to the distortion results to verify the distortion mechanism of the bearing sleeve during the quenching process.