Multifrequency composites seem to be a good approach to increase the acoustic bandwidth of standard piezoelectric composites. The mechanical coupling between the different piezoceramic elements introduces new degrees of freedom into their design. Monodimensional models have been developed to study their performances in a first approximation. In order to obtain a powerful design model, a two-dimensional model used previously to describe multielement array transducers has been extended to the case of 2-2 polymer- piezoceramic composites. Several composite samples having piezoceramic strips of different width-to-thickness ratio have been built comparing their resonance behavior with the model prediction. Finally, the model has been modified to the case of 2-2 multifrequency composites. The comparison between the experimental results and the predicted ones in the case of composites with ceramic strips of two and three different lateral dimensions is presented, showing good agreement.

This work has been partially funded by the CDTI under the project PACE-PC144.

Peer reviewed