Thermomechanical Cracking in Layered Media From Moving Friction Load

Abstract

This investigation studies a two-dimensional model of a layered medium subjected to the frictional excitation of a high-speed asperity traversing over the surface of the medium. The general analytical solutions of the mechanical stress state, the temperature field and the thermal stress state are obtained and expressed in the Fourier transform expressions. Numerical solutions are carried out for cases of uniform and parabolic pressure distributions. The resulting stress state yields the conditions for the asperity to initiate cracks in the layered medium. This paper studies further the thickness effect of the surface layer, the effect of relative stiffness of the surface layer and the substrate, and the effect of an insulating layer versus a conductive layer.