Propagation of Lamb Waves in 1-3 Piezocomposites and their Application to Liquid Sensors

摘要

This paper deals with the Lamb modes in 1-3piezocomposites. The dispersion curves in the cases where theplate is free and loaded by water, as well as the electromechanicalcoupling factor for a piezocomposite with 36 percent volumefraction of ceramic have been calculated. It is found that the firstantisymmetric mode has a very low coupling factor, whereas thatof first symmetric mode has a high value. Experimentalmeasurements of the phase velocity of the four lowest ordermodes of Lamb wave devices based on piezocomposites are foundto be in fair agreement with theory. Furthermore, as predicted bytheory, no significant attenuation of the first symmetric mode isobserved when the plate is loaded by water.