Stress intensity factor of an elliptical crack as influenced by a spherical inhomogeneity

The interaction between an elliptical crack and a spherical inhomogeneity embedded in a three-dimensional solid subject to uniaxial tension is investigated. Both the inhomogeneity and the solid are isotropic but have different elastic moduli. The Eshelby's equivalent inclusion method is applied together with the principle of superposition. An approximate solution for the stress intensity factor is obtained by an approach that expands the distance between the center of the crack and inhomogeneity in series. The local stress field can be increased or decreased depending on the relative modulus of the spherical inhomogeneity and matrix. If the inhomogeneity modulus is larger than that of the matrix, a reduction in the stress intensity factor prevails. Displayed numerically are results to exhibit the influence of inhomogeneity and its distance to the crack. © 1994.