PREPARATION OF POWDER FOR SINTERING SUPERCONDUCTING CERAMIC OF BI-ALKALINE EARTH ELEMENT-CU OXIDE TYPE

摘要

PURPOSE:To obtain the title powder for superconducting ceramic having excellent sintering properties, by calcining a coprecipitated substance prepared from a solution of Bi compound and alkaline earth element compound, blending it with a Cu compound or further an alkaline earth element compound to adjust components and calcining. CONSTITUTION:A solution of a Bi compound and an alkaline earth element compound in water or an organic solvent is mixed with a precipitate-forming agent such as caustic soda to form a suspension of coprecipitated substance consisting of a Bi component and an alkaline earth element component. A hydroxide, nitrate, organic acid salt, etc. are used as the compound. Then the coprecipitated substance is filtered off, washed, dried and then calcined at 500-950 deg.C. Then the calcined substance is mixed with a copper compound or the copper compound and an alkaline earth element compound, adjusted to the atomic ratio of Bi:alkaline earth element:Cu of 1:1-4:0.8-2.5 and calcined at 500-950 deg.C, especially 650-850 deg.C to give the aimed powder for superconducting ceramic of Bi/alkaline earth element/Cu oxide.