Two-dimensional steady-state thermal elasto-plastic contact of rough surfaces

A finite-element deterministic two-dimensional thermal elasto-plastic contact model is presented in this article, which facilitates the investigation of the influence of steady-state frictional heating on contacting asperities and subsurface stress fields. This model takes into account the asperity distortion caused by the temperature variation in a tribological process, microplastic flow of surface asperities, and coupled thermo-elasto-plastic behaviour of the material, with and without considering the strain-hardening property of the material. The model is verified through the contact analysis of a rigid, isothermal cylinder with a thermally conductive, elasto-plastic plane. The maximum contact pressures increase with frictional heating. Furthermore, thermal effects on the contact pressure, real area of the contact, and average gap of a real rough surface with different frictional heat inputs under thermal elasto-plastic contact conditions are numerically investigated. It indicates that neglecting thermal effect overestimates the real area of the contact and underestimates the average gap between the contacting surfaces.