| 摘要 |
PURPOSE:To obtain the title superconducting oxide powder having extremely low C content and superior superconducting characteristics by mixing Tl oxide powder with a compound oxide of Ca-Ba-Cu obtd. by a primary calcination of a powder mixture consisting of Ca carbonate, Ba carbonate, and Cu oxide, and calcining the mixture secondarily. CONSTITUTION:A powder mixture of powdery CaCO3, powdery BaCO3, and powdery CuO in a specified proportion is calcined primarily at 850-1050 deg.C to obtain thus a compound oxide of Ca, Ba, and Cu. Then, a specified proportion of Tl2O3 powder is mixed with the obtd. compound oxide contg. almost no C, and the mixture is calcined at 400-720 deg.C in the form of the mixture. As a result, powdery Tl-Ca-Ba-Cu-O type superconducting oxide having extremely low carbon content is obtd. Further, a ceramic material prep. from the powder has a higher critical current Jc and critical temp. Tc since there is no decrease of superconducting characteristics due to the presence of C. |
