摘要 |
PROBLEM TO BE SOLVED: To improve superconductivity by irradiating oxide superconducting powder with a predetermined microwave, and thus removing impurity in the superconducting powder to improve the sintering property. SOLUTION: Oxide superconducting powder used for a wire to be manufactured by a metal cladding method is irradiated with a microwave of 500-5000MHz immediately before charging into a metal pipe, and oxide superconducting powder using a sintered body is irradiated with a microwave of 500-5000MHz immediately before molding under pressure, thus removing impurity in the superconducting powder and cleaning the surface of the powder. By this processing, improvement in the sintering property of the superconducting powder is enabled. In the case of the oxide superconducting wire, unevenness in the superconductivity after heat treatment is reduced and reproducibility is improved by using the superconducting powder from which impurity has been removed. On the other hand, in the case of the oxide superconducting powder using a sintered body, the bulk density after heat treatment is improved and the junction property between superconducting crystals is improved, thus enabling improvement in the critical current density. |