JPH0570888B

PURPOSE:To obtain good critical current characteristics and mechanical characteristics in superconductive wire formed of Nb and Sn-based metal material and Cu-based metal material disposed around it by mixing a certain quantity of Cr in at least either the Cu- or Sn-based metal materials. CONSTITUTION:In superconductive wire obtained by applying a cross sectional contraction work and a heat process to material of Nb-based metal and Sn- based metal with Cu-based metal material disposed around it to be integrated with it, at least either the Cu-based metal material or Sn-based metal material includes 0.1-20wt% Cr. Superconductive wire of such a constitution like this is formed as below, for example. That is, in base material 6 consisting of Cu-0.8 wt%Cr alloy are embedded 90 core wires 3 of Nb, forming a composite multi- core tube including a hollow part 2 at the center. Next an Sn rod is inserted into the hollow part 2 and drawn to be 0.2mm in dia. by cold drawing. Then by heat processing this wire, Nb, Sn compound is produced on the surface of Nb filaments 4, and the base material 6 becomes Cu-Sn-Cr alloy 7 since Sn is scattered.