| 摘要 |
PURPOSE:To obtain a superconductor having a critical temp. above the temp. of liq. nitrogen and not contg. Pb by subjecting starting material consisting of compds. of Bi, Sr, Ca and Cu to calcining, melting by heating, solidification, heat treatment and quenching. CONSTITUTION:Compds. of Bi, Sr, Ca and Cu are blended in 2:2:1:2 ratio of Bi:Sr:Ca:Cu to prepare starting material and this starting material is calcined to form a precursor. This precursor is melted by heating and solidified and this solidified body is heat-treated and quenched to obtain a desired superconductor. Since the precursor is melted and solidified, the elements react actively and a denser structure than a structure formed by a powder sintering process is formed. Since the solidified body is heat-treated and quenched, the resulting superconductor has a critical temp. above the temp. of liq. nitrogen. |
