Fabrication of Bi-2223 high temperature superconducting magnet

摘要

Bi-2223/Ag alloy multifilamentary tape, whose size was 0.21 mm in thickness, 3.14 mm in width and 400 m in length, was wound to 18 pancake coils to fabricate the high temperature superconducting magnet. Each single coil had an inner diameter of 50 mm and an outer diameter of 95 mm, and consumed about 20 m long superconducting tapes coated with 10 mum thick polyester paint for insulation. The 18 pancake coils were stacked on a polyflon cylinder and the joints between each pancake coil were welded by tin solder and the copper current leads to the magnet as well. A couple of yokes had been added to the two sides of the magnet windings to decrease the radial magnetic flux density and therefore increase the I-c of the superconducting tapes. The maximum magnetic field reached 0.176 T while the I-c of the magnet was 8.16 A in the nitrogen liquid. The I-V curve, the B-I curve and the magnetic field space distribution of the magnet was tested. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 2]