Band structures of Lamb waves in one-dimensional piezoelectric composite plates: polarizations and boundary conditions

Abstract

Theoretical studies are presented for the band structures of Lamb waves in a one-dimensional phononic crystal plate consisting of piezoelectric ceramics placed periodically in an epoxy substrate. The band structures for different polarizations and electric boundary conditions are calculated for the composite plates in this paper. It is found that the first band gap is always broadened by polarizing piezoelectric ceramics, and the band gap widths with short circuit boundary condition are always larger than that with open circuit situation for the same polarization. Employing harmonic frequency analysis, the numerical results show that the Lamb wave modes corresponding to certain frequencies in the composite plates can be modulated by the different electric boundary conditions. The researches show that it is possible to control the Lamb waves in the composite plates in the engineering according to need by choosing suitable polarizations and electric boundary conditions.