Low-Temperature Sintering and Piezoelectric Properties of 0.65Pb(Zr1−xTix)O3–0.35Pb(Ni0.33Nb0.67)O3 Ceramics


  • J. L. Jones—contributing editor

†Author to whom correspondence should be addressed. e-mail: snahm@korea.ac.kr


0.65Pb(Zr1−xTix)O3–0.35Pb(Ni0.33Nb0.67)O3 (0.65PZTx–0.35PNN) ceramics exhibited a morphotropic phase boundary at approximately x=0.58–0.59. The 0.65PZT58–0.35PNN ceramics sintered at 1200°C exhibited the high piezoelectric properties of d33=605pC/N, kp=0.61, and ɛ3T0=3600. The sintering temperature of the PZT58–PNN ceramics decreased from 1200 to 850°C with the addition of a small amount of CuO. The CuO reacted with the PbO and formed a liquid phase during sintering, which assisted in the densification of the specimens. Most of the Cu2+ ions existed in the CuO second phase, thereby preventing any possible hardening effect due to the Cu2+ ions. The Curie temperature of the 0.65PZT58–0.35PNN ceramic was approximately 200°C and was not altered by the addition of CuO. The d33, kp, and ɛ3T0 values of the 0.65PZT58–0.35PNN ceramics were considerably increased with the addition of CuO and similar results were also observed for the 0.65PZT59–0.35PNN ceramics. In particular, 1.0 mol% CuO-added 0.65PZT58–0.35PNN ceramics sintered at 900°C exhibited the high piezoelectric properties of d33=620 pC/N, kp=0.64, and ɛ3T0=3750. Moreover, the reaction between the Ag electrode and the Cu-added 0.65PZT58–0.35PNN ceramic sintered at 900°C was negligible.