EVALUATION OF BIMATERIAL STRESS INTENSITY FACTORS USING A FINITE-ELEMENT BOUNDARY-ELEMENT ALTERNATING METHOD

The finite element-boundary element alternating method is extended to the analysis of a crack in a bimaterial test specimen. The crack is pe rpendicular to, and terminates at, the interface between two dissimila r materials. The finite element method is used to model the finite-siz e specimen without the crack. The displacement discontinuity method (b oundary element method) is used to find the stresses in the infinite b imaterial medium due to crack surface tractions. The stress intensity factors are extracted by using a closed form solution for a semi-infin ite crack in an infinite bimaterial medium opened by a pair of wedge f orces. The alternating method is verified by solving several bimateria l crack problems for which solutions are known. A parametric study is performed for a specimen proposed for evaluating the fracture toughnes s of bimaterial interfaces.