Bending waves in a semi-infinite piezoelectric plate with edge coated by a metal strip plate

Abstract

This work considers the propagation of bending waves along the free edge of a semi-infinite piezoelectric plate perfectly bonded with a metal strip plate of the same thickness within the framework of the first-order Reissner–Mindlin refined plate theory. The three-dimensional coupled equations for displacement fields are solved with the help of the solution to electric potential for a plate of infinite extent. The exact dispersion relation of bending edge waves is obtained. The propagation of bending edge waves in such a composite plate demonstrates multi-mode due to the presence of the metal strip plate. This wave has properties analogous to the surface wave in an elastic half-space covered by a thin layer within the theory of plane strain. The number of propagation modes depends on the width–thickness ratio of the metal plate and increases as this width–thickness ratio increases. The phase velocity of the bending edge wave in a piezoelectric composite plate is much lower than that of pure piezoelectric plate. Effect of the dimension of the metal strip plate on dispersion curves of bending edge waves is limited.