Development of Nb-Rod-Method Cu-Nb Reinforced Nb3Sn Rutherford Cables for React-and-Wind Processed Wide-Bore High Magnetic Field Coils

• Published in: IEEE transactions on applied superconductivity 2015-06, Vol.25 (3), p.1-5
• Main Authors: Sugimoto, M., Tsubouchi, H., Endoh, S., Takagi, A., Watanabe, K., Awaji, S., Oguro, H.
• Format: Article
• Language: English
• Subjects: Bronze-processed Nb3Sn wire; Integrated circuits; Nb-rod-method Cu-Nb; Niobium-tin; pre-bending effect; React-and-Wind; Rutherford cable; Strain; Stress; Superconducting cables; Superconducting magnets; Wires
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2014.2381459

We developed Cu-Nb reinforced Nb 3 Sn Rutherford cables for wide-bore high magnetic field coils that were able to be produced by React-and-Wind technique. The Cu-Nb/Nb 3 Sn strands were reinforced by internal Cu-20 vol%Nb composites fabricated by the Nb-rod-method and were manufactured through the bronze-process. The Rutherford cables composed of sixteen un-reacted Cu-Nb/Nb 3 Sn strands of 0.8-mm diameter were heat-treated at 670 °C for 96 hours. After that, repeated bending strains (pre-bending strains) were applied to the flatwise direction of the reacted Nb 3 Sn Rutherford cables at room temperature. Critical current (Ic) values of Cu-Nb/Nb 3 Sn strands extracted from the Rutherford cables were compared to those of the single strands that had undergone the same processing as the cables. I c values under the applied tensile stress of the Rutherford cable were increased by the pre-bending treatment as similar to the single strand. The performances of Cu-Nb/Nb 3 Sn Rutherford cables were improved by utilization of the pre-bending process.