Electroelastic interaction between a piezoelectric screw dislocation and a circular coated inclusion with interfacial cracks

The electroelastic interaction between apiezoelectric screw dislocation and a circular coated inclusion withinterfacial cracks is investigated. With the complex variable method,the general solutions of the complex potentials in the matrix, the coatinglayer and the inclusion regions are derived. As illustrative examples, solutions in the form of explicit series are presented in the case of one interfacialcrack. Based on the obtained complex potentials, the image force on thepiezoelectric screw dislocation is then calculated by using the generalizedPeach-Koehler formula. The equilibrium position of the dislocation isdiscussed in detail for various crack geometries, coating layer thicknessesand piezoelectric material property combinations. The results show that theinterfacial cracks have a significant perturbation effect on the motion of thepiezoelectric screw dislocation near the coated circular inclusion and thetrapping power of the coated inclusion with interfacial cracks is higherthan that of a perfectly bonded one. The critical value of the crack length or the material constant of the coating layer may be found to changethe original direction of the image force.