Investigation of the Effects of Reduced Sintering Temperature on Dielectric, Ferroelectric and Energy Storage Properties of Microwave-Sintered PLZT 8/60/40 Ceramics

In this study, (Pb0.92La0.08) (Zr0.60Ti0.40) O-3 (PLZT 8/60/40) ceramics were synthesized using a high-energy ball-milling technique followed by microwave sintering at different temperatures from 900 degrees C to 1200 degrees C. The optimal microwave sintering temperature for the PLZT 8/60/40 ceramics was found to be 1150 degrees C, which is relatively low compared with conventional sintering temperature. The sintered ceramics show the pure perovskite phase, uniform grain microstructure (1.2 mu m) and high density (similar to 99.5%). The polarization vs. electric field (P-E) hysteresis curves were used to investigate the ferroelectric and energy storage properties. The switching characteristic in P-E loops and occurrence of domain switching current in current vs. electric field (I-E) loops confirms their ferroelectric nature. The PLZT ceramics, which were sintered at 1150 degrees C, show the highest remnant polarization (P-r) of similar to 32.18 mu C/cm(2) and domain switching current (I-max) of similar to 0.91 mA with a low coercive field (E-c) of similar to 10.17 kV/cm. The bipolar and unipolar strain vs. electric field (S-E) hysteresis loops were also measured and the highest unipolar strain was found to be similar to 0.26% for the PLZT ceramics sintered at 1150 degrees C. The unipolar S-E curves were used to derive the piezoelectric coefficient (d(33 similar to)495 pm/V) and a strain hysteresis loss (similar to 5.8%).