The Interaction Between The Screw Dislocation And The Inclusion With Imperfect Interface

The electroelastic interaction of dislocation, inhomogeneity and interior defects is a greatly significative subject in the fields of solid mechanics and materials science. The force-electric coupling interaction effects between circular interfacial cracks or rigid line inclusions with imperfect interfaces and a screw dislocation located either outside or inside inhomogeneity under antiplane shear.Using Riemann-Schwarz's symmetry principle of complex functions, the above problems are transformed into Riemann- Hilbert boundary problems. By combining the analysis of singularity of complex functions, generalized Liouville's theorem, Cauchy model integral and residue theorem, the general solutions of above problems are presented. For special example, the closed form solutions for complex potentials in matrix and inhmogeneity regions are derived explicitly when interface containing single crack or rigid line, and the appropriate expressions of the electro-elastic field intensity factors at the tip of crack or rigid line are examined. Applying perturbation technique, the image force on dislocation is obtained when dislocation located arbitrary point either outside or inside inhomogeneity. The variation of screw dislocation forces for correlative material parameters and different radians of crack or rigid line is discussed particularly.As a result, analysis and discussion show that the influence of interfacial crack rigid line inclusion or imperfect interfaces on the interaction between screw dislocation and inhomogeneity is significant. With the effect of imperfect interface, cracks/rigid lines, inclusion,the image force changes to and fro. When the radian of crack reaches extensive magnitude, the presence of interfacial crack can change the interaction mechanism between screw dislocation and soft inclusion. When the radian of rigid line reaches extensive magnitude, the presence of interfacial rigid line inclusion can change not only attraction force on dislocation arisen by soft inhomogeneity into repulsion force, but also the interaction effects between screw dislocation and soft matrix. When dislocation located in piezoelectric materials or magnetoelectroelastic materials,change of the image force caused by changes of the coefficient of the imperfect interface is not large. The present solutions contain a number of previously known results which can be shown to be special cases.