JPH0345025B

A process for producing a high density ceramic of perovskite represented by the formula: ABO3 wherein A is one or more metal elements coordinated with 12 oxygen atoms, and B is one or more metal elements coordinated with 6 oxygen atoms, which comprises: (1) a step of a) preparing at least one single element solution (a solution of a modifiable element) containing the entire amount of one of the metal elements constituting the perovskite, and at least one single element solution (a solution of a modifying element) containing a part of the entire amount of another one of the metal elements constituting the perovskite, or b) preparing at least two solutions including at least one mixed solution obtained by mixing the above single element solutions at optional proportions; a step of a) forming in a single vessel an intimate precipitate mixture from said at least two single element solutions or from said at least two solutions including at least one mixed solution, in at least two steps, or b) forming separately in separate vessels precipitates from said at least two single element solutions or from said at least two solutions including at least one mixed solution and mixing the precipitates to obtain an intimate precipitate mixture; and steps of washing, drying and calcining the intimate precipitate mixture at a temperature of from 400 DEG to 1 400 DEG C. to obtain a modified oxide powder; (2) a step of mixing with the modified oxide powder a powder of a compound containing the rest of the entire amount of the modifying element and powders of compounds containing the entire amounts of metal elements constituting the peroveskite other than zirconium and the modifying element; and a step of calcining the powder mixture at a temperature of from 400 DEG to 1400 DEG C.; and (3) a step of compacting the calcined product; and a step of sintering the compacted product at a temperature of from 700 DEG to 1700 DEG C.