Effect of decohesion and sliding on bimaterial crack-tip fields

Abstract

This work is concerned with the analytical characterization of the effect of bond decohesion and sliding on the fields surrounding the tip of an interface crack. We consider the two-dimensional problem of an interface crack along the bond between a pair of linearly elastic materials. The interface itself has a nonlinear constitutive property: it has maximum load carrying capacities in both tension normal to the bond and in shear. The interface therefore has the ability to slide and separate inelastically without loss of integrity. The effects of these physically motivated assumptions are deduced and discussed. Further impetus for this study stems from the recent resurgence of interest in interfacial fracture mechanics. This interest is partly driven by the desire to understand and alleviate the pathological difficulties associated with the crack-tip fields predicted by the linear theory of elasticity. By accounting for possible interfacial nonlinear behavior, we are able to find that near-tip fields are free of the offensive properties alluded to above.