Effect of Temperature on the Sliding Wear Behaviors of Carburized BG801 Bearing Steel

The wear performance of BG801 bearing steel under elevated-temperature conditions exerts a decisive influence on the service life and operational reliability of aero-engine bearings. In this study, the vacuum low-pressure carburizing heat treatment technology was employed to perform surface carburization on BG801 bearing steel, and the effect of carburization on the frictional properties of this steel was explored over a temperature range of 25 °C to 400 °C. The results indicate that with the increase in temperature, the friction coefficients of both the uncarburized specimens (hereinafter referred to as BG801-NC) and carburized specimens (hereinafter referred to as BG801-C) are maintained in the range of 0.5~0.8. Compared with BG801-NC, the wear rate of BG801-C is reduced by approximately 50% and exhibits an overall variation tendency of increasing first and then decreasing. At elevated temperatures, BG801-C presents superior wear resistance, which is attributed to the formation of a martensite–carbide composite strengthened layer on the surface of the bearing steel after carburizing treatment, a microstructure that remarkably enhances the surface hardness and wear resistance of the steel. Moreover, the carburized layer also diminishes the thickness of the plastic deformation layer during the friction process, thereby further suppressing the extension of wear damage.