摘要
A new three-phase PZT C/PVC composite comprising PZT（50 vol%）,nanocrystalline PVC （50 vol%） and a small volume fraction f of black（C0was prepared by the hot-pressing technique.The dielectric property of the composite as α function of the frequency and the dielectric and piezoelectric properties as α function of the volume fraction f of C were studied.The measured dielectric property demonstrates that α percolation transition occurs in the three-phase composites as in normal two-phase metal-insulator continuum media.The dielectric constant varies slightly with f at f〈0.1 and increases rapidly when f is close to the percolation threshold at 1kHz.The optimum properties were obtained for f=0.5 before the percolation threshold in the PZT/C/PVC（50/f/（50-f）vol%）composite with its d33（20pC/N） being 50% higher than that of the PZT/PVC（50/50vol%）,and its g33（47.23×10^-3Vm/N）and Kp（0.25） much higher than the earlier reported values,XRD patterns and P-E hysteresis loops were used to interpret the experimental results.
A new three-phase PZT C/PVC composite comprising PZT（50 vol%）,nanocrystalline PVC （50 vol%） and a small volume fraction f of black（C0was prepared by the hot-pressing technique.The dielectric property of the composite as α function of the frequency and the dielectric and piezoelectric properties as α function of the volume fraction f of C were studied.The measured dielectric property demonstrates that α percolation transition occurs in the three-phase composites as in normal two-phase metal-insulator continuum media.The dielectric constant varies slightly with f at f〈0.1 and increases rapidly when f is close to the percolation threshold at 1kHz.The optimum properties were obtained for f=0.5 before the percolation threshold in the PZT/C/PVC（50/f/（50-f）vol%）composite with its d33（20pC/N） being 50% higher than that of the PZT/PVC（50/50vol%）,and its g33（47.23×10^-3Vm/N）and Kp（0.25） much higher than the earlier reported values,XRD patterns and P-E hysteresis loops were used to interpret the experimental results.
基金
FundedbytheNationalHighTechnologyResearchandDevelopmentProgramofChina(No.2002AA333110)
