In the aerospace industry, fretting and sliding wear are commonly encountered by components made from M50 bearing steel. This study aims to investigate the effect of temperature on the fretting and sliding wear behavior of M50 bearing steel. Research indicates that as the temperature rises from 25℃ to 350℃, the average friction coefficient decreases in fretting conditions and initially increases before decreasing in sliding conditions. At 350°C, increased oxidation occurred, resulting in the formation of oxides mainly composed of Fe₂O₃ and Fe₃O₄, with small amount of MoO₃ and Cr₂O₃. The elevated temperature causes more oxide adhering to the surface and forming a protective oxide film, thus reducing the friction and wear.

M50 bearing steel; Temperature; Fretting wear; Sliding wear