2 Tesla Class Magnet Fabrication Using Bi-2212 Ag-Sheathed Tape

摘要

Three test magnets of pancake-shaped coils using Bi-2212 tape were prepared by the wind-and-react technique. At liquid helium temperature, 16 pancake coils which were stacked in a volume of 14~φx 48~φx 75~H mm generated a magnetic field of 2.25 Tesla (T), which was within 1% of the calculated B_0. The load lines of the magnet at every temperature from 4.2 to 30K coincided with the I_c of the short tape, up to the magnetic field of 6 T. For the quadruple pancake coil, the steady-state operational current, which produced increasing voltage with the lapse of time in a cryogenic atmosphere, was a value between the critical current (I_c) determined by the criteria of 1 μV/cm and 10~(-13) Ω·m.