Critical Plane Analysis of Surface-Proximal Fields for the Simulation of Thermo-Mechanical Wear

A theory for multifield analysis of the consequences of sliding asperities on a rubber surface has been developed. The analysis considers (1) the multiaxial mechanical fields set up via the asperity contact, (2) the thermal field set up due to friction and heat generation, (3) the material property fields that evolve due to thermochemistry, and (4) the growth of crack precursors near the sliding interface. The theory considers two distinct Eulerian directions: the first direction considers strain history along streamlines oriented in the direction of sliding, and the second direction considers the progression of material toward the wear surface as material is removed. Considering the mechanical and thermal fields set up around an asperity, the theory simplifies what would otherwise be a large and complex analysis. The theory produces an estimate of the variation with depth of fatigue damage (residual life; as calculated via critical plane analysis), from which may be derived the wear rate for a particular surface sliding under a given set of conditions. Results of the calculation for two cases (two-dimensional sine wave and square wave asperity surfaces) with varying normal contact pressure are compared with Gent and Pulford’s blade abrader experiments.