THERMOELASTIC FINITE-ELEMENT ANALYSIS OF SUBSURFACE CRACKING DUE TO SLIDING SURFACE TRACTION

A linear elastic fracture mechanics analysis of subsurface crack propa gation in a half-space subjected to moving thermomechanical surface tr action was performed using the finite element method. The effect of fr ictional heating at the sliding surface on the crack growth behavior i s analyzed in terms of the coefficient of friction, crack length-to-de pth ratio, and Peclet number. The crack propagation characteristics ar e interpreted in light of results for the directions and magnitudes of the maximum shear and tensile stress intensity factor ranges, respect ively. It is shown that, while frictional heating exhibits a negligibl e effect on the crack propagation direction, it increases the in-plane crack growth rare and reduces the critical crack length at the onset of out-of-plane crack growth at the right tip due to the tensile mecha nism (kink formation). The effect of frictional heating becomes more p ronounced-with increasing contact friction, crack length-to-depth rati o, and Peclet number. Crack mechanism maps showing the occurrence of o pening, slip, and stick regions between the crack surfaces are present ed for different values of crack length-to-depth ratio, coefficient of friction, and position of thermomechanical surface traction.