SYNTHESIS AND SINTERING OF PLZT POWDER MADE BY FREEZE/ALCOHOL DRYING OR GELATION OF CITRATE SOLUTIONS

Citrate salts of PLZT 9/65/35 were prepared by drying (alcohol and/or freeze drying) and gelation of citrate solutions of PLZT. The decomposition of the citrate salts to form PLZT powder was studied by thermal analysis, X-ray diffraction, and scanning electron microscopy (SEM). It was found that the citrate salts of PLZT composition decompose in two separate stages; after decomposition, powder derived from alcohol dehydration, freeze drying and gelation have similar characteristics. Calcined powder in all cases consisted of I mu m agglomerates with a surface area of approximately 11 m(2)/g. Freeze drying and gelation are preferred over expensive alcohol dehydration. Dense pellets can be obtained from the citrate derived powder by a two stage pressureless sintering process.