Effect of LiBiO2 on low-temperature sintering of PZT-PZNN ceramics

In this study, the sintering characteristics of 0.69Pb(Zr 0.47 Ti 0.53 )O 3 -0.31Pb[(Zn 0.4 Ni 0.6 ) 1/3 Nb 2/3 ] (PZT-PZNN) ceramics after the addition of LiBiO 2 were studied. This addition lowered the sintering temperature from 1150 to 900 °C. The crystal structure changed from tetragonal to rhombohedral as the additive content increased by 0.7%. The polarization of the sintered specimen was conducted at an electric field of 3 kV/mm. When 0.7 wt% of LiBiO 2 was added and sintered at 900 °C, the piezoelectric constant ( d 33 ) was 602 pC/N; moreover, the electromechanical coupling coefficient ( k P ), sintered density, and Curie temperature ( T c ) at 1 kHz were 66.3%, 7.99 g/cm 3 , and 252.8 °C, respectively. When 0.7 wt% of LiBiO 2 was added, the PZT-PZNN ceramic showed an increased strain curve of 0.118% at 2 kV/mm. The interdiffusion between the copper (Cu) electrode and ceramic material was not observed in the scanning electron microscopy (SEM) results; thus, the possibility of manufacturing an actuator using a Cu electrode using a novel composition was confirmed. The actuator displacement with the voltage 400 V was 1.2 μm. The thickness of the multi-layered actuator was 1 mm. Through this, the possibility of manufacturing a multi-layered actuator with a Cu electrode was confirmed through the composition of 0.69PZT-0.31PZNN (LiBiO 2 0.7 wt%).