Analytical modeling and experimental verification of the depth of subsurface heat-affected layer in gear profile grinding

The excessive grinding temperature usually causes grinding burns characterized by hardness change, microstructure change, and residual tensile stress, and the grinding damage commonly exists in a specific depth range below the ground surface. In order to examine the depth of the heat-affected layer on the gear tooth profile after grinding, the grinding temperature distribution in the workpiece during grinding is evaluated by utilizing a newly established profile grinding thermal model first. Subsequently, the threshold temperature of grinding burn under various grinding conditions is determined by introducing the tempering parameter (i.e., Hollomon Jaffe parameter). Finally, a prediction model for the depth of the heat-affected layer on the sub-surface of the gear tooth profile is established by considering the special contact relationship between the grinding wheel and gear tooth profile. The gear single tooth profile grinding experiment is then carried out, and the proposed model is successfully verified by detecting the cross-section burn and microstructure distribution of the gear tooth after grinding. The effects of grinding process parameters on the distribution of the heat-affected layer on the sub-surface of the tooth profile are investigated. The obtained results reveal that the proposed prediction model can precisely estimate the distribution of heat-affected layers in tooth profile cross-section after gear profile grinding.