This note presents the stress intensity factors of a long crack penetrating a circular transforming inhomogeneity. Using the Greens functions of dislocations interacting with a circular inhomogeneity experiencing an isotropic (free expansion) eigenstrain, the elasticity solution is reduced to a system of singular integral equations representing the traction boundary condition along the crack surfaces. The normalized stress intensity factor, obtained through a numerical solution of the integral equations, has a strong dependence on the elastic mismatch, and can be either negative or positive depending on the crack-tip location. The formulation and results generalize a previously published transformation-toughening model that assigns equal elastic moduli to the inhomogeneity and the surrounding medium.

Issue Section:
Brief Notes
Keywords:
surface cracks, crack-edge stress field analysis, transformation toughening, elastic moduli, Green's function methods, dislocations
Topics:
Dislocations, Fracture (Materials), Stress, Elastic moduli
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Copyright © 2004
 by ASME
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