Analysis of Interfacial Fracture in Thin Films Subjected to Thermal Loading

We consider the problem of a three-dimensional interface crack between a film and a substrate to gain a better understanding of how the problem of peeling in film-substrate material systems subjected to thermal loading can be alleviated. We assume that the crack lies in the plane of the interface and is located at one of the free comers of the structure. The fracture parameters (mixed mode stress intensity factors, phase angles and the energy release rate) along the crack front are obtained using an interaction energy integral technique developed by Gosz et al. (1998) for analysis of three dimensional, bimaterial interface cracks. The technique is a very accurate domain integral method that is employed as a post-processing step after a finite element solution for the stress, strain, and displacement fields in the solid has been obtained. In the paper, we investigate the effect of film thickness on the fracture parameters and the results are discussed.