PURPOSE: To obtain the title superconductor improved in temperature beginning to manifest superconductivity and critical temperature by mutually formulating Bi, Sr and Cu as principal components at specified molar ratio.
CONSTITUTION: A starting material is prepared by mutually formulating Bi2O3, SrCO3 and CuO so as to be 1±0.05:2±0.05:2±0.1 in the molar ratio Bi:Sr:Cu. This material is then put to wet mixing, ground and dried, followed by calcina tion at ca.800°C for ca. 12hr, and the resultant product is ground to produce an oxide superconductor material composition. Thence, this composition is formed using e.g. a mold press, thus obtaining the objective oxide superconductor ca. 37.5K in the temperature Tconset beginning to manifest superconductivity and ca. 28K in the critical temperature Tczero.
SUMIYA KEIJI
KUWAJIMA HIDEJI
ASHIZAWA TORANOSUKE
YAMANA SHOZO
