Dynamic Anti-Plane Behaviors Of A Semi-infinite Piezoelectric Medium With Circular Cavities

Due to piezoelectric materials possess high degree of high power density, greater efficiency and potential for low cost manufacture, so they arewidely 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 coupling electro-mechanical loads. The presence of various defects, such as dislocations, cracks and inclusions, can greatly influence their characteristics and coupling behavior. Therefore, it is very important to study the electro-elastic fields as a result of the presence of defects.An analytic method based on the theory of linear elasticity is developed for the problem of scattering of steady SH-wave and dynamic analysis on a piezoelectric medium with multi-cavity near the interface in this paper. The scattered wave function, which satisfies the condition of stress free at the surface of a piezoelectric semi-infinity with multi-cavity near the surface impacted by using complex function theory and multi-polar coordinate method. Furthermore, the problem can be summarized to the scattering of SH-wave by a semi-infinite piezoelectric medium with multi-cavity near the interface with the help of this wave function. The complex variable function series which approach the solution of that problem and general expression for boundary conditions are given. Numerical examples are provided to show the effect of the geometry of the cavities, the piezoelectric parameters of the materials, the frequencies of the incident wave and different ratio of the distance between the cavity's center and the interface to the cavity's radius upon the dynamic stress concentration factors. This paper indicates the influence of the electro-mechanical coupling upon the dynamic stress concentration factors.