Development and performance of a 2.9 Tesla dipole magnet using high-temperature superconducting CORC® wires

Author(s): Wang, X; Abraimov, D; Arbelaez, D; Bogdanof, TJ; Brouwer, L; Caspi, S; DIetderich, DR; DImarco, J; Francis, A; Garcia Fajardo, L; Ghiorso, WB; Gourlay, SA; Higley, HC; Marchevsky, M; Maruszewski, MA; Myers, CS; Prestemon, SO; Shen, T; Taylor, J; Teyber, R; Turqueti, M; Van Der Laan, D; Weiss, JD | Abstract: Although the high-temperature superconducting (HTS) REBa2Cu3O x (REBCO, RE-rare earth elements) material has a strong potential to enable dipole magnetic fields above 20 T in future circular particle colliders, the magnet and conductor technology needs to be developed. As part of an ongoing development to address this need, here we report on our CORC® canted cosθ magnet called C2 with a target dipole field of 3 T in a 65 mm aperture. The magnet was wound with 70 m of 3.8 mm diameter CORC® wire on machined metal mandrels. The wire had 30 commercial REBCO tapes from SuperPower Inc. each 2 mm wide with a 30 µm thick substrate. The magnet generated a peak dipole field of 2.91 T at 6.290 kA, 4.2 K. The magnet could be consistently driven into the flux-flow regime with reproducible voltage rise at an engineering current density between 400-550 A mm-2, allowing reliable quench detection and magnet protection. The C2 magnet represents another successful step towards the development of high-field accelerator magnet and CORC® conductor technologies. The test results highlighted two development needs: continue improving the performance and flexibility of CORC® wires and develop the capability to identify locations of first onset of flux-flow voltage.