Superconducting Property Evaluations of Bi2223 Tapes in Winding
高温超伝導線材の巻線時性能劣化の評価
We designed and are fabricating a cryocooler-cooled 19 T superconducting magnet consisting of NbTi coils, Nb3Sn coils and a Bi2223 insert coil. The insert coil is made up for 25 double pancake coils. The inner diameter and the outer diameter of each double pancake coil are 90 mm and 180 mm, respectively. In order to investigate the mechanical properties of the double pancake coils, two double pancake coils were exited in liquid helium in the back up fields up to 11 T and hoop stresses were applied to the double pancake coils. As the results, the superconducting properties of the double pancake coils did not degrade even after the hoop stress application of 143 MPa, which is exceeding the hoop stress applied in the 19 T superconducting magnet.
Toshiba Co.: K. Tasaki, M. Ono, M. Kyoto, S. Hanai
IMR, Tohoku University: K. Watanabe, S. Awaji, G. Nishijima, K. Koyama, K. Togano
Reference: K. Tasaki, M. Ono, T. Kuriyama, M. Kyoto, S. Hanai, H. Takigami, H. Takano, K. Watanabe, S. Awaji, G. Nishijima and K. Togano, "Development of a Bi2223 insert coil for a cryocooler-cooled 19 T superconducting magnet", to be presented in ASC 2004.
冷凍機冷却19 T超電導マグネットの開発を行っている．マグネットの最内層に配置されるBi2223超電導コイルの機械的特性を評価するために，実機コイルと同サイズのダブルパンケーキコイル2個で構成されたR&Dコイルを作製し，11 T中でフープ力印加試験を実施した．19 Tマグネットで印加されるフープ力を超えた143 MPaを印加した後でも，R&Dコイルの超電導特性に劣化が生じないことを確認した．
東芝：田崎賢司, 小野通隆, 京藤　誠, 花井　哲
東北大学　金属材料研究所：渡辺和雄, 淡路　智, 西島　元, 小山佳一, 戸叶一正