Abstract:

Both theoretical analysis and experimental practice have shown that an appropriate distribution of residual compressive stress on machined surface can improve the surface quality of machine parts and prolong the contact fatigue life. In order to eliminate the residual stress on the outside race surface of bearing ring, this paper uses the pre-stress hard cutting method to initiatively control the residual stress state on the bearing rings surface and hence to improve the fatigue life. Three different processing methods for bearing rings, namely the hard dry cutting, the pre-stress hard cutting and the grinding are then implemented by experiments, and the corresponding residual stress and hardness of the machined surface are compared and analyzed. Moreover, the morphology and texture characteristics of the machined surface are investigated. The results indicate that the pre-stress hard cutting helps to obtain suitabe residual compressive stress state and good surface quality for the machined surface of bearing rings.

Key words: pre-stress, hard cutting, residual stress, surface morphology, fatigue strength