Effect of Microwave Sintering on Electrical Properties of PLZT Ceramics

Lead lanthanum zirconate titanate(PLZT) powders synthesized by partial co-precipitation method were used to fabricate PLZT ceramics by conventional muffle furnace or by microwave muffle furnace. The crystal structure, microstructure, electrical properties of PLZT ceramics prepared by these two methods were investigated. The results show that the PLZT ceramics sintered by these two methods are pure perovskite structure. Microwave sintered PLZT ceramics possess smaller grain, more uniform size and less holes than do the conven tional prepared. The microwave sintering temperature is much lower than that by the conventional method, and the duration time is also much less, while the electrical properties of the ceramics sintered by these two methods are similar. The best properties of PLZT ceramics can be gained by microwave sintering at 1000℃ with dielectric constant and piezoelectric constant of 2512 and 405 p C/N. The remnant polarization is 16.5 k V/cm, and the coercive field is 8.2 μC/cm2. The dielectric constant and piezoelectric constant of PLZT ceramics sintered by conventional method at 1250 ℃reach the maximum values of 2822 and 508 p C/N. The remnant polarization is 21.6 k V/cm and the coercive field is 9.6 μC/cm2.