US Patent 7210216 Method of producing superconducting wire

A method of producing Nb3Sn superconducting wire, including the steps of: preparing a plurality of Sn modules obtained by burying Sn-based metal cores in a Cu-based metal matrix and a plurality of Nb modules obtained by burying Nb-based metal filaments in a Cu-based metal matrix; bundling the Nb modules and the Sn modules such that the Nb modules surround the Sn modules and obtaining an assembly; inserting the assembly in a tubular member of Cu-based metal which internally comprises tube-like shaped Ta-based metal or Nb-based metal which serves as a diffusion barrier and obtaining a composite; drawing the composite; and heat-treating the composite.