Patent ID: 7459031

Claim:
A method for producing an Nb 3 Sn superconductive wire material using a powder process, comprising: filling a powdered raw material in a sheath made of Nb or an Nb-based alloy, subjecting the sheath to diameter reduction to form a wire, and performing heat treatment for the wire to form a superconductive layer at the interface between the sheath and the filled powder, wherein the powdered raw material contains powdered Sn, powdered Cu, and a powdered alloy or powdered intermetallic compound, which is formed from Sn and at least one metal selected from the group consisting of Ti, Zr, Hf, V, and Ta, respectively, and when the amount of the powdered alloy or the powdered intermetallic compound is assumed to be 100, the amounts of the powdered Sn and the powdered Cu in the powdered raw material are 15 to 90 mass percent and 1 to 20 mass percent, respectively.