Determination of Stress Intensity Factors for Interfacial Cracks in Bimaterial Systems

Abstract

A relatively simple numerical method was developed to determine the stress intensity factors of interfacial cracks in bimaterial systems. The method is based on the evaluation of crack tip stress components using a p-version finite element method. Numerical experiments on a number of specimen geometries covering a wide range of material combination were performed. The geometries tested include a center-cracked panel (CCP), a single-lap shear joint (SLS) having two anti-symmetric cracks at the edges, a four-point bend specimen, and a bonded double-cantileverbeam (DCB) specimen. The numerical results agreed well with the analytical solutions and the experimental data of certain geometries. The range of integration distance over which accurate stress intensity factors can be determined was found to be within 10−5 and 10−3 of crack length and seems to be geometry independent.