| 摘要 |
PURPOSE:To obtain a multiple perovskite type oxide ceramic constituted of uniform and fine crystal particles without causing loss of components in a stage of preparation by mixing a compound oxide prepd. by a coprecipitation method to a compsn. with a separately prepd. metal oxide having another compsn., and calcining the mixture. CONSTITUTION:An aq. soln. contg. plural kinds of water-soluble metal compds. selected from nitrates and hydroxides of metal elements of A site or B-site constituting a multiple perovskite type compd. expressed by the formula (wherein each A and A' is a 1-2 valent metal; each B and B' is a 2-6 valent metal). A coprecipitate is generated by adding aq. ammonia to the aq. soln., and the coprecipitate is treated in a rotary evaporator or in a spray dryer to remove thus a solvent. Thereafter, obtd. dry powder is calcined provisionally and an A-site or B-site multiple oxide is formed, which is weighed exactly and mixed with separately prepd. and exactly weighed B-site or A-site metal oxide, and the mixture is calcined. Thus, a multiple oxide ceramic having a compsn. expressed by the formula is obtd. |
