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Sn wires with and without Cu-Nb reinforcement中本 美緒*; 菅野 未知央*; 荻津 透*; 杉本 昌弘*; 谷口 諒*; 廣瀬 清慈*; 川崎 卓郎; Gong, W.; Harjo, S.; 淡路 智*; et al.
IEEE Transactions on Applied Superconductivity, 34(5), p.8400806_1 - 8400806_6, 2024/08
被引用回数：0 パーセンタイル：0.00(Engineering, Electrical & Electronic)For an accelerator magnet, a certain mechanical strength is required to sustain against a transverse compression stress due to Lorentz force. A bronze-route NbSn wire with Cu-Nb reinforcement was developed by Tohoku University and Furukawa Electric to enhance the strength against axial tension. The Cu-Nb reinforcement wire also exhibited some indication of strength improvement against transverse compression; however, the details of a reinforcement mechanism for the transverse compression stress have not been clarified. In this study, the internal strains of NbSn bronze-route wires with and without the Cu-Nb reinforcement under transverse compression stress were evaluated by neutron diffraction at BL19 (TAKUMI) in J-PARC. The samples were attached to jig with solder only at the ends and compression was applied at the center of the samples with 30-mm anvil with 5-mm wide and 8- to 15-mm high beam. Since a critical current, Ic of a superconducting wire depends on the three-dimensional strain, internal strain of NbSn along the axial and two orthogonal radial directions were evaluated at room temperature (RT). In the different setup, Ic measurements of the wires under transverse compression stresses were also performed at 4.2 K and 14.5 T. Using 3-mm wide anvil, the transverse compression was applied at 4.2 K or RT. The neutron diffraction results indicated no significant differences in the internal strains of NbSn under transverse compression between the samples with and without Cu-Nb reinforcement, while the Ic measurements showed potential increase in the irreversible stress (
) for Cu-Nb reinforced wires. The reason for this discrepancy was discussed based on the difference in the experimental setups for each measurement.
Sn cable-in-conduit conductors辺見 努; Harjo, S.; 伊藤 崇芳; 松井 邦浩; 布谷 嘉彦; 小泉 徳潔; 高橋 良和; 中嶋 秀夫; 相澤 一也; 鈴木 裕士; et al.
IEEE Transactions on Applied Superconductivity, 21(3), p.2028 - 2031, 2011/06
被引用回数：10 パーセンタイル：48.89(Engineering, Electrical & Electronic)熱処理温度923Kから運転温度5KまでのNbSn素線とステンレス鋼の熱膨張率の違いによって導体内には残留歪が生じる。NbSn素線の超伝導特性は残留歪の状態によって大きく変化するため、その特性を評価するためには残留歪の状態を把握する必要がある。しかし、複雑な構造とジャケット材の内側に素線が配置されているため、導体内の素線の歪を直接測定した研究はこれまでない。一方、J-PARCで2008年から運転が開始された工学材料回折装置「匠」は中性子回折を用いて歪として相対精度0.02%で測定することが可能である。本研究では、匠による中性子回折をITER TF導体の残留歪の測定に適用した。中性子回折では格子面間隔の変化により導体内の各相の歪を決定することが可能である。これにより、素線の残留歪の発生機構及び歪状態と超伝導性能の関係を明らかにすることが可能となった。
伊藤 崇芳; Harjo, S.; 長村 光造*; 辺見 努; 淡路 智*; 町屋 修太郎*; 小黒 英俊*; 西島 元*; 高橋 弘紀*; 松井 邦浩; et al.
Materials Science Forum, 681, p.209 - 214, 2011/05
被引用回数：1 パーセンタイル：50.51(Materials Science, Multidisciplinary)The construction of the engineering materials diffractometer TAKUMI at J-PARC has been finished at the end of March 2009, and user programs have been started since January 2009. We proposed a project research with the title of "Stress/strain effects on industrial superconducting composites", and have carried out several preliminary experiments at TAKUMI. This project research aims to clarify internal strains behaviors in industrial superconducting materials generated due to their processes and/or during uses, and to understand the relation between the internal strains and their superconducting properties. Our interests are in developments of superconducting (Nb
Sn, NbAl, etc.) strands and HTC tapes, and in developments of superconducting (ITER and LHC) cables (composing many superconducting strands or tapes and other stabilizing and/or strengthening materials). In this opportunity, we will report our project research status more details.
YCuO
系における構造的な乱れと物性茂筑 高士*; 畑 慶明*; 星川 晃範*; 岩瀬 謙二*; Sulistyanintyas, D.*; 小黒 英俊*; 石垣 徹*; 井川 直樹; 土屋 佳則*; 岩井 秀夫*; et al.
no journal, ,
FeSrYCuO系には、CuとFeの相互置換,酸素欠損を要因とする構造的な乱れがあり、超伝導と反強磁性的な磁気秩序の発現に大きく影響している。本報では、中性子回折により構造的な乱れや低温での構造変化を解析し、構造的な乱れと、超伝導,磁性との関連を議論する。
