An investigation was made of the interaction between screw dislocations, which were located at arbitrary points within the matrix or the inhomogeneity, and a circular coated inhomogeneity with two imperfect interfaces. Explicit solutions of the stress fields and strain energy were derived. With the aid of the Peach-Koehler formula, explicit expressions for the image forces acting upon the dislocations were derived for certain cases. The mobility of the screw dislocation in the matrix was considered with regard to parameters such as interface imperfection, material mismatch and dislocation position, and the influence of nearby dislocations was also considered. The attractive force acting on the screw dislocation, produced by the imperfect interfaces, was expected to increase with an increase in the degree of interface imperfection. In addition, the mobility and stability of the screw dislocation were strongly influenced by nearby dislocations. The basic solutions provided could be used as Green’s functions in order to solve problems involving the interaction between an arbitrarily shaped crack and a coated inhomogeneity with imperfect interfaces.

Screw Dislocations Interacting with a Coated Inhomogeneity Containing Two Imperfect Interfaces. Q.H.Fang, Y.W.Liu, T.X.Liu, P.H.Wen: Physica Status Solidi B, 2008, 246[1], 32-44