Dielectric and Piezoelectric Properties of Low-Temperature-Sintering Pb(Mg1/2W1/2)O3-Pb(Ni1/3Nb2/3)O3-Pb(Zr,Ti)O3 Ceramics for Multilayer Piezoelectric Actuator

In this study, in order to develop low-temperature-sintering ceramics for a multilayer piezoelectric actuator, Pb(Mg 1/2 W 1/2 )O 3 -Pb(Ni 1/3 Nb 2/3 )O 3 -Pb(Zr,Ti)O 3 (PMW-PNN-PZT) ceramics were fabricated using Li 2 CO 3 and CaCO 3 as sintering aids and their dielectric and piezoelectric properties were investigated in relation to the amount of Bi substitution. Piezoelectric actuators require both a high piezoelectric constant ( d 33 ) and a high electromechanical coupling factor ( k p). Accordingly, in this study, Bi was substituted at the Pb site of basic composition PMW-PNN-PZT ceramics for the enhancement of k p and d 33 . With increasing Bi substitution, density gradually increased. At the sintering temperature of 900°C, the electromechanical coupling factor ( k p) and piezoelectric constant ( d 33 ) of PMW-PNN-PZT composition ceramics with 1.0 mol % Bi substitution as well as 0.2 wt % Li 2 CO 3 and 0.25 wt % CaCO 3 showed the optimal value of 0.618 and 473 pC/N, respectively, for multilayer piezoelectric actuator application.