金属系超電導線材 [1]

— 研究開発のあゆみ —

抄録

In the past decade, there has been significant progress in the production and application of metallic superconductors. The production of Nb-Ti wires for LHC facilities, totaling approximately 7,000 km in length, has been completed. The fabrication of NB₃Sn wires for ITER facilities, totaling some 500 t in weight, is underway. The high-field performance of Nb₃Sn wires has been appreciably enhanced, facilitating the generation of 20 T at 4.2 K. Today, Nb₃Al wires that are fabricated using an improved process are approaching practical use. Newly developed MgB₂ wires are also being developed with the aim of applications at 20K. In the present course, the recent status of these metallic superconductors will be described. As an introduction, this article outlines the chronological progress of metallic superconductors. Progress has been made through basic research on electromagnetic and material aspects, as well as through the development of new fabrication processes. A personal comment regarding the development of metallic superconductors is also briefly mentioned in this article.