PERMITTIVITY AND ELECTRICAL-CONDUCTIVITY OF PZT P(VDF-TRFE)-0-3 COMPOSITES/

The permittivity at 1 kHz and the d.c. conductivity of lead zirconate titanate (PZT)/vinylidene-trifluoroethylene [72/28 P(VDF-TrFE)] copoly mer 0-3 composites have been measured from 30 degrees C to 140 degrees C. Abrupt changes in both the permittivity and electrical conductivit y were observed at different temperatures upon heating and cooling, re vealing a thermal hysteresis phenomenon. The observed permittivity and electrical conductivity were compared with the predictions of the Bru ggeman model and good agreements were found. The ratio of electric fie lds experienced by the ceramic and copolymer during poling was estimat ed from the measured permittivity and electrical conductivity and an o ptimum poling procedure was selected to polarize the 0-3 composites.