Rough surface and damage mechanics wear modeling using the combined finite-discrete element method

In this investigation the combined finite discrete element method was used to analyze fretting wear of rough and smooth Hertzian contacts using the Archard wear equation and continuum damage mechanics. Surface roughness profiles were generated using the Voronoi tessellation procedure and scaled in order to analyze the effect of roughness on fretting wear. Using the Archard equation, wear loss increased with roughness in the partial slip regime. In contrast, in the gross slip regime roughness only played a role at the beginning of a test before all of the asperities had been removed. Using the damage mechanics, subsurface damage accumulation was found to be a linear function of cycles. In this approach, a long breaking-in period occurred before the first wear particles were detached from the surface; however, following initiation, wear loss was approximately a linear function of cycle number. The shape and evolution of fretting wear scars were in agreement with experimental results.