Composite Material Dislocation And A Circular Inclusion Force Of Interfacial Defects, Electrical Interference Effect

The electroelastic interaction of dislocation, inhomogeneity and interior defects is a greatly significative subject in the fields of solid mechanics and materials science. The interaction effects between circular interfacial cracks or rigid line inclusions and a screw dislocation located either outside or inside inhomogeneity under antiplane shear, the electroelastic interaction between a piezoelectric screw dislocation located either outside or inside inhomogeneity and circular interfacial cracks and rigid lines under longitudinal mechanical and inplane electrical loads in linear piezoelectric materials and The elastic interaction between an edge dislocation located either outside or inside inhomogeneity and interfacial crack along a circular inhomogeneity are dealt with in this paper.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, however, a number of previous related investigations on above problems only calculated the interactive dislocation force as the dislocation lies on the x-axis. 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 or rigid line inclusion on the interaction between screw dislocation and inhomogeneity is significant. When the radian of crack reaches extensive magnitude, the presence of interfacial crack can change the interaction mechanism between screw dislocation andsoft 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. Soft inhomogeneity can repel screw dislocation in piezoelectric material due to their intrinsic electromechanical coupling behavior. The influence of crack geometrical dimension and materials elastic constants on edge dislocation force is evaluated and discussed when dislocation is located in matrix. It is shown that the interfacial crack has a significant effect on the equilibrium position of the edge dislocation near circular interface. The results also exhibit a strong dependency different between the shear modulus and Poisson's ratios of the matrix and the inclusion. The present solutions contain a number of previously known results which can be shown to be special cases.