| 摘要 |
PURPOSE:To obtain the subject superconductor having a high volume ratio in the superconducting phase at the high critical temperature and critical current density by thermally melting a raw material for a Bi-Sr-Ca-Cu based oxide superconductor, quenching the melt and heat-treating the resultant quenched substance under specific conditions. CONSTITUTION:A raw material for a Bi-Sr-Ca-Cu based oxide superconductor (e.g. simple substance or compound, such as oxide or carbonate, of the respective constituent elements) is calcined, mixed so as to provide a composition satisfying the formula Bi2Sr2Ca2Cu3Ox and melted while being heated, quenched at a quenching rate within the range of, e.g., 1X10<2>-1X10<7> deg.C/sec, to provide a quenched substance having partially disordered orientation of crystal lattices. The resultant quenched substance is then rapidly heated to temperature conditions of 400-800 deg.C at, e.g. about 10-1,000 deg.C/min heating rate, in an O2- containing atmosphere, then heat-treated under the same temperature conditions for a long period and crystallized to produce a phase of the high critical temperature. |
