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公开(公告)号:IN175115B
公开(公告)日:1995-04-29
申请号:IN168DE1988
申请日:1988-03-07
Applicant: IBM
Inventor: BEYERS ROBERT BRULE , ENGLER EDWARD MARTIN , GRANT PAUL MICHAEL , LIM GRALE SU
IPC: C01G1/00 , C01G3/00 , C04B35/00 , C04B35/45 , H01B12/00 , H01B13/00 , H01L39/12 , H01L39/24 , B22F1/00
Abstract: Compositions having the formula A1+/-xM2+/-xCu3Oy, wherein A is Y, or a combination of Y La, Lu, Sc or Yb; M is Ba, or a combination of Ba, Sr or Ca and y is sufficient to satisfy the valence demands, have been found to be bulk electrical superconductors at a temperature above 77K. The compositions are single phase perovskite-like crystalline structures. They are made by a process involving intimately mixing the metal oxides or their precursors in the proper molar ratios, heating the mixture in the presence of oxygen to a temperature between about 800 DEG C and about 1100 DEG C and slowly cooling the mixture to room temperature in the presence of oxygen over a period of at least four hours.