Bonded dissimilar strips with a crack perpendicular to the functionally graded interface

The mode I crack problem for two dissimilar infinite strips bonded through a functionally graded interfacial zone is investigated within the framework of plane elasticity. The graded interfacial zone is treated as a nonhomogeneous continuum, having the continuously varying elastic modulus between the dissimilar homogeneous strips. A crack is assumed to be embedded in one of the strips perpendicular to the nominal interface. With the aid of the stiffness matrix approach, a set of homogeneous conditions relevant to the proposed crack problem is readily satisfied. Subsequent application of the mixed conditions on the cracked plane then leads to a singular integral equation of the first kind which is solved numerically. In consequence, the variations of stress intensity factors are provided as functions of geometric and material parameters of the bonded structure. The effect of the material nonhomogeneity in the interfacial zone is further addressed by measuring the degree of correspondence with the results that are obtained based on the use of the homogenized interfacial elastic property. Copyright (C) 1996 Elsevier Science Ltd.