Crack-tip fields for cracks perpendicular to the interface between dissimilar elastic and creeping materials

The stress fields at the tip of a crack terminating at and perpendicular to the interface under symmetric in-plane loading are investigated. The bimaterial interface is formed by a linearly elastic material and an elastic power-law creeping material. Using generalized expansions at the crack tip in each region and matching across the interface, a series asymptotic solution is constructed for the stresses and strain rates near the crack tip. It is found that the stress singularities, to the leading order, are the same in each material, oscillatory higher-order terms exist in both regions, and stress higher-order term with the order of O(r°) appears in the elastic material. The stress exponents and the angular distributions for singular terms and higher order terms are obtained for different hardening exponents. A full agreement between asymptotic solutions and the full-field finite element solutions has been obtained.