| 摘要 |
PURPOSE:To obtain the title Bi-Sr-Ca-Cu-O-based superconductor with reduced baking temperature without causing decrease in its superconductivity critical temperature by adding a fluoride to the raw material. CONSTITUTION:Bi2O3, SrCO3, CaCO3, CuO and a fluoride (e.g. CaF2) are weighed so as to be 1:1:1:2 in the molar ratio Bi:Sr:Ca:Cu, mixed and ground. The amount of the fluoride to be added is pref. such as to be ca. (20:1)-(1:1) in the molar ratio based on the raw material component such as Bi, Sr or Ca. Thence, the resulting powder is calcined at 800-850 deg.C, baked at 830-880 deg.C, and further heat treated in air or oxygen gas stream to obtain the objective fluorine-incorporated bismuth-based oxide superconductor. Thus, a superconductor predominant in 110K-class high-temperature phase can be produced at baking temperatures lower than those conventionally used. |
