The coupling interaction of a piezoelectric screw dislocation with a bimaterial containing a circular inclusion

The coupling interaction of a piezoelectric screw dislocation with a bimaterial containing a circular inclusion is investigated by the complex potential method and conformal mapping technique. Explicit series solutions are obtained and then cast into new expressions with the coupling interaction effects separated. The new expressions converge much more rapidly and their one-order approximation formulae have satisfactory accuracy in many cases. According to the generalized Peach–Koehler formula, the image force acting on the screw dislocation is explicitly obtained and numerically studied to reveal the coupling interaction arising from multiple material properties as well as the geometry of inhomogeneous phases. In all regions, the coupling interaction has a significant influence on the number, location and stability of dislocation equilibrium points. In particular, the inclusion can reverse the image force within a region in the material on the other side of the interface.

Screw Dislocations Emitted from a Blunt Crack in a Piezoelectric Material

The problem of a piezoelectric screw dislocation emitted from a blunt crack is dealt with in this paper. For an arbitrary distribution of the residual dislocation, the series-form solutions are derived. The results show that the force acting on the dislocation decreases with the value of the dielectric constant within the crack increasing. And the increase of the dielectric constant within the crack helps dislocation emission effectively.