Scattering Of SH-Wave And Dynamic Stress Concentration On A Piezoelectric Medium With An Inclusion Near The Interface

Piezoelectric materials possess high degree of high power density, greater efficiency and potential for low cost manufacture in comparison with alternative electromechanically coupled materials. As a result, the applications of piezoelectric materials have given rise to the remarkable progress of sensors and actuators used in the self-controlling and self-monitoring smart structures. Therefore, it is of very importance to study the electro-elastic fields as a result of the presence of defects.An analytical 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 an inclusion near the interface in this paper. The scattered wave function, which satisfies the condition of traction free at the surface of a piezoelectric semi-infinity with a cylindrical inclusion near the interface under incident steady SH-wave, is constructed based upon the symmetry of SH-wave scattering and the method of multi-polar coordinates. Furthermore the problem can be summarized to the scattering of SH-wave by a semi-infinite piezoelectric medium with an inclusion near the interface with the help of this wave function. Then the scattering of time harmonic SH-wave and the dynamic stress concentrations in a piezoelectric medium with a cylindrical inclusion near the interface are studied with the help of complex variable theory and wave function developing method. The theoretical analyses reveal how the stress fields depend upon the intensity of incident wave and electric field, as well as the ratio of the distance between the inclusion's center and the interface to the inclusion's radius. And the expressions of dynamic stresses at the cylindrical inclusion's edge are obtained. At last, the solution of the problem can be reduced to a series of algebraic equations and can be solved computationally by truncating the finite terms of the infinite algebraic equations. The calculating cases are obtained and plotted with different wave numbers, different piezoelectric characteristic parameters and different ratio of the distance between the inclusion's center and the interface to the inclusion's radius. The calculating results show that dynamic analyses are very important to a semi-infinite piezoelectric medium with a cylindrical inclusion near the interface at lower frequencies and larger piezoelectric characteristic parameters.