Residual stress evolution for tooth double-flank by gear form grinding

Abstract

In gear form grinding, the complexity of tool-workpiece geometries affects the grinding force and heat distribution along the tooth profile, thus resulting in difficulties in the calculation of residual stress. Specifically, the stress and heat generated on the newly machined tooth flank were influenced by the former grinding passes. Unfortunately, this issue was ignored in the previous research. To fill this gap, this paper presents a thermal-mechanical coupling calculation model considering the differences in gear double-flank, and a new heat source optimization algorithm is proposed. Firstly, according to the kinematic analysis of gear form grinding, the Lagrange interpolation method is used to solve unevenly distributed moving heat sources on the curved surface. Secondly, based on the theory of plastic increment combined with the von Mises yield criterion considering work hardening, the relationship between the temperature and the grinding stress on the first grinding tooth flank and the second grinding tooth flank is obtained through load cyclic loading. Finally, the residual stress field in the final state of all tooth flanks is obtained through the release procedure. The gear grinding experiments were conducted to verify the model, and the comparison results showed good consistency. The influence of unevenness in gear form grinding is not only reflected in the stress distribution along the tooth profile, but also on the different flanks. Based on the correlation law between the processing parameters and the residual stress on the tooth flanks, the optimal machining parameter range is obtained. The study provides an important reference for the understanding of gear form grinding mechanisms and the optimization of the grinding process.