PHENOMENOLOGICAL MODEL OF FRICTION ACCOUNTING FOR SUBSURFACE PLASTIC DEFORMATION IN METAL FORMING

摘要

The paper deals with the effect of subsurface plastic deformation on the evolution of the real contact area and on friction in metal forming processes. A model of evolution of real contact area is derived within a phenomenological framework by considering a thin homogeneous surface layer representing the asperities and the layer of inhomogeneous deformation induced by deforming asperities. The friction model is then derived by assuming asperity flattening and ploughing mechanisms to occur at different scales.