Hard piezoelectrics with high dielectric and piezoelectric constants are used for high-power applications. However, the sintering temperature of these ceramics is high, around 12001C, restricting the usage of cheap base metal electrodes in fabrication of multi-layer components. This study investigates the effect of CuO and ZnO on the sintering temperature of a hard piezoelectric, APC 841, which is a MnO 2 -and Nb 2 O 5 -modified PZT. The addition of CuO decreased the sintering temperature through the formation of a liquid phase. However, the piezoelectric properties of the CuO-added ceramics sintered at r9501C were lower than the desired values. The addition of ZnO resulted in a significant improvement in the piezoelectric properties. This enhancement was attributed to the formation of a homogeneous microstructure with large grains. The APC 84110.2 wt% CuO11.1 wt% ZnO ceramics sintered at 9501C showed excellent piezoelectric and dielectric properties with values of k p 5 0.532, Q m 5 750, d 33 5 351 pC/N, e 33 /e o 5 1337, and T c 5 2801C.
D. Damjanovic-contributing editor