Lamb wave suppression in periodic 1-3 piezoelectric composite transducers

This paper investigates suppression of Lamb waves in piezoelectric composite transducers by matching their frequency to the even harmonics of the device thickness mode. This was done by a combination of experimental measurement on a number of transducers along with simulations using the finite element code PzFlex. Both 2-2 and 1-3 composites made from the single crystal materials pzn-4.5%pt and pzn-8%pt were investigated along with composites made from pzt5h ceramic. The theory is supported by means of experimental impedance analysis and laser scanning of surface displacement, with good agreement demonstrated