Piezoelectric and pyroelectric properties of 65PMN-35PT/P(VDF-TrFE) 0-3 composites

摘要

Lead magnesium niobate-lead titanate (PMN-PT with 35 mol percent PT) ceramic powder fabricated using the Columbite method have been incorporated into a polyvinylidene fluoride-trifluoroethylene (P(VDF-TrFE) 70/30 mol percent) copolymer matrix to form 0-3 composites. With the composition near the morphotrophic phase boundary (MPB) region, PMN-PT has high piezoelectric properties as a result of the enhanced polarizability arising from the coupling between two equivalent energy states. P(VDF-TrFE) ferroelectric copolymer films can be poled to give piezoelectric and pyroelectric performance without prior mechanical stretching. The composites with both phases being ferroelectric were prepared using solvent casting to disperse the ceramic powder homogeneously in the copolymer matrix. Composites with PMN-PT volume fraction ranging from 0.05 to 0.4 were fabricated. The piezoelectric and pyroelectric coefficients of the composites were studied as a function of ceramic volume fraction phi under different poling conditions. Both the piezoelectric and pyroelectric coefficients of the PMN-PT/P(VDF-TrFE) 0-3 composites were found to be higher than that of the PZT/P(VDF-TrFE) 0-3 composites.