| 摘要 |
<p>A method for manufacturing a high-temperature superconducting wire having a reduced AC loss and having a predetermined shape. A high-temperature superconducting filament (14) is produced by filling a tube (10) ((a)) having a first oxygen-permeable metal layer (11) of a silver alloy and an oxidizable metal layer (12) of magnesium and so forth with a powder of the material of a high-temperature superconductor ((b)). A plurality of such tubes (10) are bundled ((d)). The bundle is rolled and formed ((e)), and heated to 400 to 800°C in an oxygen atmosphere. As a result, oxygen is supplied to the oxidizable metal layer (12) from the first oxygen-permeable metal layer (11), and the oxidizable metal layer (12) is oxidized to become a barrier layer (17) ((f)). The bundle is heated to 780 to 840°C in a mixture gas atmosphere containing oxygen and nitrogen or argon the oxygen partial pressure of which is 5 to 30%. The material in the high-temperature superconducting filaments (14) reacts to become a Bi2223 high-temperature superconductor (141) ((g)). In the thus produced high-temperature superconducting wire (18), the current between the high-temperature superconducting filaments (14) is reduced, and the coupling loss, which is a kind of AC loss, is also reduced. Even after the rolling step ((e)), the barrier layer (17) (the oxidizable metal layer (12)) is not yet oxidized and still has plasticity. Therefore, the wire can be formed into a predetermined shape.</p> |
