Patent ID: 9680081
Date: 2017-06-13
CPC Classifications: H01B,H01L,Y10T

Claim:
1. A precursor wire for producing an Nb 3 Al superconducting wire by rapid-heating, quenching and transformation processes, comprising an assembly of a plurality of single wires, the assembly being covered with an outer cover (skin) formed from Nb or Ta, wherein each of the single wires comprises an Nb/Al composite filament region which is formed from a composite of Nb and Al mixed in an Nb:Al molar ratio of 3:1, an interfilamentary barrier formed from Cu or Ag covered on the outside of the Nb/Al composite filament region for effectively electromagnetic decoupling of superconducting filaments, and a partition formed from Nb or Ta provided between the Nb/Al composite filament region and the interfilamentary barrier for preventing the interfilamentary barrier from reacting with the Nb/Al composite filament region to form a non-superconducting compound, wherein the volume fraction of Cu or Ag in the single wire is 7 to 25%, and wherein, when Cu is used as the interfilamentary barrier, Ta film having a thickness of 5 μm or more is used as the partition, and, when Ag is used as the interfilamentary barrier, Nb or Ta film having a thickness of 1 μm or more is used as the partition.