Dielectric and piezoelectric properties of lead zirconate titanate doped with chromium oxide

Abstract

Vector impedance measurements of radial modes of thin disks (diameter 13 mm and thickness 1 mm) of Pb(Zr0.515Ti0.485)O3 doped with Cr2O3 have been carried out using an impedance analyzer. Piezoelectric equivalent circuit parameters R, L, Ca in series, and Cb in parallel have been measured by simulating ‖Z‖ and θ plots. Piezoelectric parameters for the first four radial modes have been obtained and it is found they peak at about 0.32 mol % of Cr2O3. The piezoelectric coupling coefficient Kp has been correlated with the dielectric constant. The dielectric quality factor Qe and mechanical quality factor Qm have been measured and (Qe/Qm)<1. ac conductivity follows a frequency power law with exponent p<1, suggesting that the hopping mechanism may be responsible for the dielectric loss.