Wear behavior and damage characterization for AISI 52100 bearing steels: Effect of hardness and spherical carbides

Abstract

The current trend of increasing the precision lifetime of high-performance bearings forces scientists and engineers to optimize the heat treatment and processing technology to endure higher fatigue frequencies from rolling/sliding motion. In this study, the influences of two crucial factors, hardness and spherical carbides, on the wear behavior of AISI 52100 bearing steel were investigated using elaborate heat treatments to control the variables. The results showed that avoiding excessive hardness and improving the content of spherical carbides could reduce the wear volume during sliding friction and enhance wear resistance. On the one hand, high hardness is correlated to high carbon concentration and high micro-plastic strain in the martensite matrix, inducing the propagation of microcracks and formation of large-size shallow micro-pitting, which accelerates wear loss. On the other hand, spherical carbides effectively inhibit severe plastic deformation of the martensite matrix, which inhibits the wear loss caused by micro-cutting and decreases the formation of wear debris. In this case, densely distributed carbides can improve the wear performance.