THE FREE-END INTERFACE CRACK PROBLEM FOR BONDED ORTHOTROPIC LAYERS

The plane elasticity problem of two bonded orthotropoic layers containing cracks perpendicular to and along the interface is considered. The cracks are extended to intersect the boundaries and each other in such a way that a crack configuration suitable to study the edge debonding problem associated with bonded dissimilar materials is obtained. The problem is reduced to the solution of a system of singular integral equations with Cauchy type singularities. Numerical results for stress intensity factors and energy release rates are presented for various loading conditions and for isotropic as well as orthotropic material pairs. These results indicate that elementary strength of material type calculations for energy release rates provide a very good approximation to the actual elasticity solution even for relatively short cracks under some practical loading conditions such as thermal loading, as long as the thicknesses of the layers are not very different.