Improved Hot-Pressed Electrooptic Ceramics in the (Pb,La)(Zr,Ti)O3 System

Physical, electrical, and optical properties of selected compositions within the lead lanthanum zirconate-titanate (PLZT) system are presented, including chemically and thermally etched microstructures, examples of residual porosity defects, temperature dependence of remanent polarization and coercive field, lateral switching strains, and thermal expansion and optical transmission data. Optical-quality ceramics were produced by stringent raw material selection and improved ceramic processing and hot-pressing. Optimum results were obtained from starting oxides with higher purity (99.9%) and smaller particle size (<2 μm) than those used in previous investigations. These oxides were processed by methods developed to minimize segregation and promote chemical homogeneity and hot-pressed at temperatures (1050° to 1250°C) higher than those used previously to remove residual porosity.