POLYMER-CERAMIC COMPOSITES FOR PIEZOELECTRIC SENSORS

Polymer/ceramic composites with 0-3 connectivity have been produced by introducing fine-grain modified lead titanate powder in the matrix of a copolymer of vinylidene fluoride and trifluorethylene (VDF/TrFE). T he electromechanical coupling factor k(t), the acoustic impedance Z0 a nd the mechanical quality factor Q(m) of these films are determined. k (t) values in the range 30-35% have been achieved. Ultrasound transduc ers have been fabricated with these films. The impulse response of the transducer in the transmitting mode is determined. An attempt has bee n made to produce a theoretical model to match the experimental observ ations.