ELASTIC WAVE PROPAGATION IN PIEZOELECTRIC/PIEZOMAGNETIC BI-MATERIAL PLATES

Elastic wave propagation in a bi-material plate that consists of a piezoelectric layer and a piezomagnetic layer is investigated. Both layers are transversely isotropic and perfectly bonded along the interface. The upper and lower surfaces of the plate are traction-free but subjected to four types of electromagnetic boundary conditions. The general solutions for governing equations of piezoelectric and piezomagnetic materials are derived by using the partial wave method. According to the interfacial and boundary conditions, the dispersion equations are given in matrix form. Numerical examples are provided for four kinds of the bi-material plates composed of piezomagnetic CoFe2O4 and piezoelectric BaTiO3, PZT-5A, PZT-2 and PZT-4, respectively. The influences of the electromagnetic boundary conditions, the thickness ratio of piezoelectric layer to piezomagnetic layer as well as piezoelectric materials properties on dispersion characteristics are discussed. The results are helpful for the applications of piezoelectric/piezomagnetic composites or structures in acoustic wave and microwave devices.