Stress Intensity Factor for a Planar Interfacial Crack in Three Dimensional Bimaterials

Abstract

In this paper, stress intensity factors for a three dimensional planar interfacial crack are considered on the idea of the body force method. The formulation leads to a system of singular integral equation, whose unknowns are three types of crack opening displacements. The unknown body force densities are approximated by the products of the fundamental density functions and power series; here, the fundamental density functions are chosen to express singular stress fields due to a two-dimensional interface crack exactly. The calculation shows that the present method gives rapidly converging numerical solutions. It is found that the stress intensity factors K I and K II are determined by bimaterials constant ε alone, independent of elastic modulus ratio and Poisson's ratio.

Variations of Stress Intensity Factors of a Planar Interfacial Crack Subjected to Mixed Mode Loading

“…In the preceding papers [12], [13], it is found that the stress intensity factors are controlled by bimaterial constant ε alone under tensile loading. In Table 3, Poisson's ratio and shear modulus ratio are changed under constant value of ε =0.02.…”

“…In the preceding papers [12], [13], a rectangular crack under tension was analyzed and smooth distributions of SIFs were obtained. Although the problem of an interface crack in a dissimilar material is expressed as a system of singular integral equations by Chen-Noda-Tang [14], it is difficult to solve the equations precisely considering the overlap of crack opening displacement and stress oscillation singularity, which are peculiar to interfacial cracks.…”