Design, fabrication and performance of a 1.29 T Bi-2223 magnet

The design and fabrication procedure of a laboratory-scale Bi-2223 tape sup erconducting magnet with a bore of 40 mm and a maximum field of 1.29 T at 4 .2 K is presented. The magnet comprises six resin impregnated double-wound pancakes of bore diameter 40 nim fabricated via the react-and-wind route. C ritical current density (J(c)) measurements have been made as a function of magnetic field, angle and strain at 4.2 K and 77 K on short samples. In ze ro field, the critical current density for the superconducting cross-sectio nal area of the tape was 8.3 x 10(4) A cm(-2) (4.2 K) and 1.18 x 10(4) A cm (-2) (77 K). The electric field-current density characteristics of all the components of the coils when individually energized or with the whole magne t energized have been measured. Comparison between short sample measurement s and performance of the magnet show that minimal additional damage occurre d beyond the similar to 20% that was produced by the bending strain during the wind-and-react fabrication procedure and the similar to 10% variation o f the long length J(c) of the tape. Sufficient detail is provided for the n on-specialist to assess both the use of potential brittle superconducting t apes for magnet technology and to construct a laboratory-scale magnet.