Subsurface residual stress and damaged layer in high-speed grinding considering thermo-mechanical coupling influence

Abstract

Subsurface residual stress and damaged layer play a vital role in determining the accuracy maintenance and fatigue performance of parts. Due to the advantages of machining quality and efficiency, high-speed grinding technology is being applied to the machining of precision parts. At present, the influence of high-speed grinding on the damaged layers generation and residual stress distribution has not been completely recognized, and there has been little quantitative research on the mechanism of thermo-mechanical coupling influence on the distribution of residual stress generated in the high-speed grinding process. In this study, a finite-element model comprehensively considering grinding force and thermal field was proposed to investigate the subsurface residual stress and heat influenced layer of AISI 52,100 bearing steel. The subsurface damaged layer and residual stress fields were measured to validate the analytical results. Mathematical models were proposed to quantitatively analyze the thermo-mechanical coupling influence on the distribution characteristics of subsurface residual stress. The theoretical and experimental results demonstrate that when the grinding speed surpasses the critical value of 45 m/s, the depth of residual stress and damaged layer decrease simultaneously with the increase of grinding speed. Higher grinding speeds exceeding 60 m/s are supposed to restrain the maximum value of both the tensile and compressive residual stress, which helps to enhance the precision retention and fatigue performance of components. Base on this study, the performance of the subsurface can be controlled by selecting the proper grinding speed in the high-speed range.