Title :
A 6 T refrigerator-cooled NbTi superconducting magnet with 180 mm room temperature bore
Author :
Urata, M. ; Kuriyama, T. ; Yazawa, T. ; Koyanagi, K. ; Yamamoto, K. ; Nomura, S. ; Yamada, Y. ; Nakagome, H. ; Murase, S. ; Maeda, H. ; Horigami, O.
Author_Institution :
Res. & Dev. Center, Toshiba Corp., Kawasaki, Japan
fDate :
6/1/1995 12:00:00 AM
Abstract :
A 6 T NbTi superconducting magnet, cooled by a 4 K GM (Gifford-McMahon) refrigerator has been developed. Magnetic material, Er/sub 3/Ni, is used as the regenerator to cool the coil to liquid helium temperature. The central field strength in the 180 mm room temperature bore is designed to be 6 T. NbTi coil dimensions are, 215 mm in inner diameter, 279 mm in outer diameter, and 240 mm in axial length. The coil winding is an epoxy-impregnated structure without a bore tube, thereby reducing mechanical disturbances. The coil heat is removed through the outer metal cylinder. A pair of Bi(2212) current leads has been developed to reduce heat leakage into the 4 K level. A cold diode is used to protect the coil even if the oxide lead is burned out. The magnet attained 6.45 T central field at 3.61 K coil-winding temperature.<>
Keywords :
cooling; niobium alloys; refrigeration; refrigerators; superconducting magnets; titanium alloys; 180 mm; 215 mm; 240 mm; 279 mm; 3.61 K; 4 K; 6 T; 6.45 T; Bi(2212) current leads; Er/sub 3/Ni; Gifford-McMahon refrigerator; NbTi; central field strength; coil winding; epoxy-impregnated structure; heat leakage reduction; liquid helium temperature; mechanical disturbances reduction; refrigerator-cooled NbTi superconducting magnet; room temperature bore; superconducting coil cooling; Boring; Erbium; Magnetic liquids; Magnetic materials; Niobium compounds; Refrigeration; Superconducting coils; Superconducting magnets; Temperature; Titanium compounds;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
