A FRACTAL MODEL FOR THE RIGID-PERFECTLY PLASTIC CONTACT OF ROUGH SURFACES

In this study a continuous asymptotic model is developed to describe t he rigid-perfectly plastic deformation of a single rough surface in co ntact with an ideally smooth and rigid counter-surface. The geometry o f the rough surface is assumed to be fractal, and is modeled by an eff ective fractal surface compressed into the ideally smooth and rigid co unter-surface. The rough self-affine fractal structure of the effectiv e surface is approximated using a deterministic Canter set representat ion. The proposed model admits an analytic solution incorporating volu me conservation. Presented results illustrate the effects of volume co nservation and initial surface roughness on the rigid-perfectly plasti c deformation that occurs during contact processes. The results from t his model are compared with existing experimental load displacement re sults for the deformation of a ground steel surface.