Critical current densities of high- T c Bi(Pb)-2223 wire-in-tube, continuous-tube-forming/filling and silver-alloy double-pancake coils at 77 K

• Published in: Applied superconductivity Vol. 4; no. 7; pp. 343 - 347
• Main Authors: Vo, N.V., Liu, H.K., Dou, S.X.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 1996
• ISSN: 0964-1807; 1879-1530
• DOI: 10.1016/S0964-1807(97)00007-0

Critical currents of superconducting silver and silver-alloy composite double pancake coils of Bi 1.80Pb 0.33Sr 1.87Ca 2.00Cu 3.00O x have been measured at liquid nitrogen temperature. A critical current density of ~ 12.5 kA/cm 2 was measured for a coil fabricated from Bi(Pb)-2223/Ag composite tape of length ~2.2m (~342 Ampere-turns) using the wire-in-tube method. For coils made from alloys of silver (e.g. ~0.02% magnesium), higher critical currents (~ 17 A) have been achieved over those fabricated with tapes processed with pure silver matrix. Transport measurements of normalised J c vs B in fields up to 1 T show encouraging results for wire-in-tube and continuous-tube-forming/filling composite tapes prepared with rolling as the intermediate deformation. These results indicate the feasibility of “high- T c ” superconducting magnets in some engineering applications.