Thermal-induced surface damage of M50 steel at rolling-sliding contacts

The thermal-induced surface damage of M50 steel at rolling-sliding contacts under heavy load and high speed is investigated. A two-disk test rig is used for testing the surface damage of M50 steel at scuffing. The thermal response and near-surface deformation of M50 steel at rolling-sliding contacts are analyzed based on its high-temperature properties. The results show that the surface damage of M50 steel at rolling-sliding contacts is basically caused by thermal softening of near-surface material, which is generated by the heat of both the friction and plastic deformation. A high temperature due to the frictional heat at rolling-sliding contacts first reduces the yield strength of M50 steel. A large plastic deformation of near-surface material is therefore generated, which, in turn, causes a large temperature rise. Scuffing occurs at a quick increase in thermal softening of M50 steel.