Designs and Prospects of Bi-2212 Canted-Cosine-Theta Magnets to Increase the Magnetic Field of Accelerator Dipoles Beyond 15 T

Journal Article · 21 March 2018 · IEEE Transactions on Applied Superconductivity

DOI: https://doi.org/10.1109/TASC.2018.2818278 · OSTI ID:1563954

Garcia Fajardo, Laura  ^[1]; Brouwer, Lucas  ^[1]; Caspi, Shlomo  ^[1]; Gourlay, Stephen ^[1]; Prestemon, Soren  ^[1]; Shen, Tengming  ^[1]

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1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

The critical current density of Bi-2212 round wires has seen significant improvement over the past two years. We present the magnetic design and stress analysis of two Bi-2212 dipoles based on Canted-Cosine-Theta (CCT) technology using the state-of-the-art wires. The first design, based on a 19-strand Rutherford cable of θ0.8mm strands, is a two-layer dipole with a bore diameter of 40 mm and an outer diameter of 98.4 mm; it generates 5.4 T when operating in stand-alone configuration and 18.9 T in 15 T background field. The second design, based on a 13-strand Rutherford cable of θ0.8mm strands, is also a two-layer dipole with a bore diameter of 40 mm and an outer diameter of 81 mm; it generates 4.0 T when operating in stand-alone configuration and 17.8 T in 15 T background field. Normal stresses on the conductor in these magnets do not exceed 35 MPa when working under background field.Moreover, we propose a novel approach for increasing the efficiency of CCT magnets using keystoned Rutherford cable while removing the midplane ribs. with this method, it is possible to increase the efficiency of small radius CCT coils by 20%. We conclude that Bi-2212 can be used to increase the limit of accelerator magnet dipole fields beyond 15 T while managing stresses in the coils to acceptable levels.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 1563954
• Journal Information: IEEE Transactions on Applied Superconductivity, Journal Name: IEEE Transactions on Applied Superconductivity Journal Issue: 4 Vol. 28; ISSN 1051-8223
• Publisher: Institute of Electrical and Electronics Engineers (IEEE)Copyright Statement
• Country of Publication: United States
• Language: English