The Acoustic Impedance and other Properties of (1-3) Piezoceramics Polymer Composite

摘要

The work is focused on an attempt to develop a route for the fabrication of piezoceamic-polymer composites having (1-3) type connectivity. The process included the extrusion of rods of diameter approximately 200 μm. A commercial piezoelectric, PC-5 was modified by addition of a lithium/bismuth based glass former together with excess PbO to lower the sintering temperature to about 1000°C. The fast firing sintering was employed. The rods were assembled and impregnated with an epoxy resin to form 1-3 composites containing approximately 50 and 20 vol% piezoceramic. The measurement values showed that, the piezoelectric constant, d_(33) = 232 pCN~(-1) and 215 pCN~(-1), thickness electromechanical coupling coefficient, k_t = 0.51 and 0.5 and the mechanical quality factor, Q_m = 14 and 5 for the composites containg PZT rods at 50 vol% and 20 vol% respectively. Their acoustic impedances were 5.1 and 3.6 for the 50 vol% and 20 vol% of PZT rods respectively. The results show that with lower volume% of PZT could result in lower acoustic impedance which can be further improved for biomedical imaging and hydrophone applications.