Dielectric, piezoelectric and structural studies on the intermediate composition region of Pb(Zn1/3Nb2/3)O3-PbZrO3 ceramics

Binary solid solutions of the xPb(Zn1/3Nb2/3)O-3-(1 - x)PbZrO3 system were synthesized by the conventional ceramic process, where both constituents are not ferroelectric in their ceramic forms. Various physical properties of highly dense ceramic specimens with various compositions were investigated. As a result, structural conversion between the perovskite and the pyrochlore phase was found to occur in the range of x = 0.4 to 0.7. In this region, the ratio of the perovskite to the pyrochlore phase increased with the increase in sintering temperature. and relaxor-type ferroelectricity was observed. Dielectric constants were also found to be very sensitive to the variation in the ratio of these two phases. A ferroelectric perovskite single phase was shown to exist in the range of x of approximately 0.1 to 0.4. Maximum values obtained are as follows: remanent polarization P-r 28.8 muC/cm(2), electromechanical coupling factors k(31) = 11.0%, k(p) = 18.8% and k(33) = 37.2%, and piezoelectric constants d(31) = 20.9 x 10-(12) C/N and d(33) = 74.1 x 10(-12) C/N.