Dynamic Anti-plane Behaviors Of An Infinite Piezoelectric Medium With Multi-circular Cavities

Due to this intrinsic coupling behavior, piezoelectric materials are widely used in modern technology such as high power sonar transducers, electro-mechanical actuator, piezoelectric power supplies and micro-positioner. These devices are designed to work under combined electro-mechanical loads. The presence of various defects, such as dislocations, cracks cavities and inclusions, can make great influence on their characteristics and coupled behavior. Therefore, it is of very importance to study the electro-elastic fields as a result of the presence of defects.This paper constitutes a continuing study in understanding the microscopic behavior of these materials in the presence of defects such as cracks, dislocations, cavities and inclusions subjected to mechanical and electrical loads. In this paper, the dynamic interaction between holes in an infinite piezoelectric medium under anti-plane mechanical and in-plane electric loads was investigated by using complex variable function and multi-polar coordinate method. The complex variable function series which approach the solution of that problem and general expression satisfying boundary conditions are given. Numerical examples are provided to show the effect of the geometry of the holes, the piezoelectric parameters of the materials and the frequency of the incident wave upon the dynamic stress concentration factor. The calculating results reveal the importance of electro-mechanical coupling terms upon the problem of dynamic stress concentrations.