| 摘要 |
PURPOSE:To obtain the title superconductor of 110 deg.K grade by preliminary calcination, under specified conditions, of raw material mixed powder followed by grinding, mixing, calcination and then heat treatment in a low-temperature oxygen atmosphere. CONSTITUTION:A mixture comprising oxide, nitride and carbonate, or raw material mixed powder with the atom ratio Bi:Sr:Ca:Cu=1:1:1:1.5-2.0 produced by coprecipitation technique is preliminarily calcined at 800-880 deg.C for 3-10hrs followed by grinding and mixing and then forming. Thence, the resultant form is calcined at 800-880 deg.C for 10-100hrs to produce a sintered form, which is then heat-treated at low temperatures of 300-600 deg.C in an oxygen atmosphere of 1-200atm for 10-30hrs. |
