High critical currents in cold-powder-metallurgy-processed superconducting Cu-Nb-Sn composites

Abstract

Cold‐powder‐metallurgy‐processed superconducting Cu‐Nb‐Sn (discontinuous) multifilamentary composites have been fabricated. Overall critical current J_c comparable to the best in situ and commercial multifilamentary Nb₃Sn (scaled for the same Nb content) have been achieved. Values of J_c approximately 10⁵ A/cm² at 12 T, 5×10⁴ A/cm² at 14 T, and 2×10³ A/cm² at 18 T are observed for a material with Cu–40 wt.% Nb–20 wt.% Sn with respect to Cu. The physical characteristics of the starting materials and some advantages of the cold‐powder‐metallurgy process are discussed.