Property improvement of 0.3Pb(Zn1/3Nb2/3)O3-0.7Pb0.96La0.04(ZrxTi1−x)0.99O3 ceramics by hot-pressing

The piezoelectric ceramics of the compositions expressed by the formula: 0.3Pb(Zn1/3Nb2/3)O3-0.7Pb0.96La0.04(ZrxTi1−x)0.99O3 (x = 0.50–0.53) were prepared by two kind of sintering processes: conventional sintering (CS) and hot-pressing (HP) sintering. By comparing the properties of these two series of ceramics, piezoelectric coefficients (d33), electromechanical coupling factors (kp), dielectric constants (ɛr), etc. were enormously improved by HP sinter procedure, which can be attributed to the highly dense microstructure (bulk density >99%). The most impressive results are the d33 (845pC/N) and kp (0.703) in the HP specimen with Zr/Ti = 51/49, which have not been observed in the previous relative reports. Additionally, according to the contrast of the experiment data, the origin of the property improvement was analyzed in details.