Patent ID: 8571616

Claim:
A compound sheath superconducting wire comprising: a metal base wire member with a Vickers hardness of at least 50 at room temperature, wherein the metal base wire member includes iron, a plurality of tubular-shaped metal cladding layers having a superconductor material coaxially provided within the tubular-shaped metal cladding layers, wherein each of the metal cladding layers has an electric resistance of 7μΩcm or less at room temperature, each of the tubular shaped metal cladding layers being arranged to be provided within the metal base wire member in parallel with each other along a longitudinal direction of the metal base wire member prior to a drawing step to form the compound sheath superconducting wire, and an intermediate layer coaxially provided outside the tubular-shaped metal cladding layers, wherein the intermediate layer is electrically and mechanically unified metallurgically with the metal base member and the tubular-shaped metal cladding layers in a unitary block such that a gap is not formed between the metal base wire member and the tubular-shaped metal cladding layers by a drawing step to form the compound sheath superconducting wire, the intermediate layer as a brazing material is an alloy made by both tin and at least one of copper, silver, gold, palladium, aluminum, silicon, zinc, iron, nickel, manganese and boron.