Unidimensional modeling of 1-3 composite transducers

Abstract

Composite transducers, utilizing the complementary properties of a piezoelectric ceramic and a polymer, often possess acoustic matching and electromechanical efficiency that are superior to conventional isotropic materials. The extent of the performance enhancement is a complex function involving composite design in conjunction with external electrical and mechanical loading conditions. This work uses an established modeling technique, supported by finite element analysis and experimental observation, to predict the mechanical, electrical, and piezoelectric properties of 1-3 composite structures. These parameters are then combined in a modified thickness-drive model to predict the performance of composite probe assemblies under realistic operating conditions. Accurate correlation between simulation and experimental results is demonstrated over an extensive range of ceramic-polymer volume fraction. Significantly, the results suggest that composites that possess relatively high-volume fractions of ceramic are superior to the lower volume fraction devices on which previous work has concentrated.