Cryogenic cooling effect on surface and subsurface microstructural modifications in burnishing of Co–Cr–Mo biomaterial

The aim of the present work is to investigate the effect of a severe plastic deformation (SPD) process, cryogenic burnishing, on the surface integrity modifications of a Co–Cr–Mo alloy due to the burnishing-induced surface integrity properties. A set of experiments was conducted to investigate the influence of different burnishing parameters on distribution of grain size, phase structure and hardness of the processed material. The results from this work show that the proper selection of burnishing conditions can significant improve the surface integrity of the Co–Cr–Mo alloy due to refined microstructure, high hardness, and favorable phase structure on the surface layer, which could potentially lead to advanced wear performance of such material.