Numerical simulations for the phase velocities and the electromechanical coupling factor of the Bleustein-Gulyaev waves in some piezoelectric smart materials

In this paper, the propagation behavior of the surface Bleustein-Gulyaev (B-G) waves in a piezoelectric layered half-space is investigated. The governing equations of the coupled waves are obtained. The boundary conditions are assumed in such a way that the displacements, shear stress, electric potential, and electric displacements are continuous across the interface between the layer and the substrate together with the traction-free boundary at the surface of the layer. The electrically open and short conditions at the surface are adopted to solve the problem. The phase velocity is numerically calculated for the electric open and short cases for different thicknesses of the layer and wave number. The phase velocity equation of the B-G wave is obtained by an analytical technique when a layered half-space with an identical piezoelectric layer and substrate but with opposite polarization is utilized. The electromechanical coupling factor in the layered piezoelectric structures is discussed. The results obtained in this paper will be very useful for the engineering application of B-G waves.