Abstract
Currently, good precision is established by the grinding process used for machining the parts. However, there are still uncontrollable steps to this process, such as the apparition of some damage, in which the major deterioration is from the residual stress. In order to investigate the residual stress caused by mechanical stress, thermal stress and phase transformation stress, using the grind-hardening test of 40Cr and the residual stress test, the residual stress distributions under different grinding parameters were obtained. In addition, numerical simulation for the thermal stress of the workpiece surface was carried out by ANSYS, and then the distribution of phase transformation stress under different grinding parameters was deduced. The research shows that grinding parameters have significant influence on the distribution of residual stress at the hardening layer.