Properties and microstructures of PLZT ceramics hot-pressed from commercial powders

Abstract Chemical-prepared 9/65/35 PLZT powders were hot-pressed in oxygen and air atmosphere at a temperature of 1200°C and pressure of 200 kg/cm2 for 20 hours. X-ray fluorescence analyses. D—E hysteresis tests and Curie-point measurements were made on such fabricated samples. It was found that the compositions of these powders are different from the expected value of 9/65/35 (La/Zr/Ti). Although a maximum transparency of 68.2% was obtained for the specimen hot-pressed in an oxygen atmosphere, due to the compositional non-uniformity, it was not possible to measure the electrooptic coefficient. The microstructure observations revealed that La2O3-4PbO precipitates formed at grain boundaries of the samples made from the powder added with 10 wt% excess PbO. The formation of La2O3-4PbO precipitates was also investigated in this paper.