Assessment of critical factors affecting the performance of trapped field magnets using thin film superconductor tapes

Trapped field magnets have been investigated using Zr-added (Gd,Y)Ba-Cu-O thin film superconductor tapes. Trapped field profiles were examined both experimentally and by simulation over a temperature range of 30 to 77 K. A good match is found between experimental and simulation trapped field data at 77 K and 65 K, but higher trapped field values were obtained experimentally at lower temperatures. Trapped field values up to 1.55 T were measured in an 11 mm thick stack of 55 um thick superconductor tapes arranged in a crisscross fashion with three tapes per layer. A substantial increase in the trapped field values was found by simulation, in tape stacks made with 20 um thick tapes. Using such thin tapes, trapped field values of nearly 2 T is predicted in [?] 13 mm thick tape stacks at 77 K.