- Wang, Xiaorong;
- Bogdanof, Timothy J;
- Ferracin, Paolo;
- Ghiorso, William B;
- Gourlay, Stephen A;
- Higley, Hugh C;
- Kadiyala, Janakiram Kaushal;
- Kar, Soumen;
- Lee, Reginald;
- Luo, Linqing;
- Maruszewski, Maxwell A;
- Memmo, Robert;
- Myers, Cory S;
- Prestemon, Soren O;
- Sandra, Jithin Sai;
- Selvamanickam, Venkat;
- Teyber, Reed;
- Turqueti, Marcos;
- Wu, Yuxin
A dipole magnet generating 20 T and beyond will require high-temperature superconductors such as Bi2Sr2CaCu2O 8 − x and REBa2Cu3O 7 − x (RE = rare earth, rebco). Symmetric tape round (star®) wires based on rebco tapes are emerging as a potential conductor for such a magnet, demonstrating a whole-conductor current density of 580 A mm−2 at 20 T, 4.2 K, and at a bend radius of 15 mm. There are, however, few magnet developments using star® wires. Here we report a subscale canted cos θ dipole magnet as an initial experiment for two purposes: to evaluate the conductor performance in a magnet configuration and to start developing the magnet technology, leveraging the small bend radius afforded by star® wires. The magnet was wound with two star® wires, electrically in parallel and without transposition. We tested the magnet at 77 and 4.2 K. The magnet reached a peak current of 8.9 kA, 78% of the short-sample prediction at 4.2 K, and a whole-conductor current density of 1500 A mm−2. The experiment demonstrated a minimum viable concept for dipole magnet applications using star® wires. The results also allowed us to identify further development needs for star® conductors and associated magnet technology to enable high-field rebco magnets.