AN AXISYMMETRICAL CRACK IN BONDED MATERIALS WITH A NONHOMOGENEOUS INTERFACIAL ZONE UNDER TORSION

In this study the mode III axisymmetric crack problem for two dissimilar homogeneous materials bonded through a thin layer of nonhomogeneous interfacial region is considered. The shear modulus of the interfacial layer is assumed to be mu(2)(z) = mu(1) exp (alpha z). If is also assumed that mu(3) = mu(1) exp (alpha h), h being the thickness of the layer and mu(1) and mu(3) the shear moduli of the adherents. The main results of the study are the stress intensity factors, the strain energy release rates and to a limited extent, the crack-opening displacements obtained as functions of the two primary variables h/a and mu(3)/mu(1) under various lending conditions, where a is the radius of the crack. Some results are also presented for a penny-shaped crack in an unbounded nonhomogeneous medium.