Abstract: A method for joining two or more superconducting wires each comprising a bundle of filaments of tin (Sn) and niobium (Nb) contained within a binder metal with a superconducting joint. The filaments on the ends of the wires to be joined are first exposed by etching the binder metal away with acid and then the exposed filaments are intertwined. The exposed filaments are then sealed in a copper-enriched chamber and heated to a temperature and for a time sufficient for the Sn and Nb to diffuse together and form Nb.sub.3 Sn at their interface. Preferably, the filaments are sealed by forming a tubular jacket, placing the tubular jacket over the exposed filaments and the wire ends adjacent thereto, and swaging the ends of the tubular jacket to the wire ends adjacent the exposed filaments.

Abstract: A method is disclosed for fabricating a wire from niobium tin produced in situ in a filamentous structure capable of achieving the superconducting state which comprises overlapping a tin alloy core comprised of tin-magnesium eutectic alloy with alternating layers of copper and foraminous layers followed by drawing the thus-formed niobium filaments into wire, then heating the wire at sufficiently high temperature to cause the eutectic alloy to homogeneously diffuse through the length of the copper wire and rods to react with the Nb, forming the A-15 crystal structure of Nb.sub.3 Sn, characterized by refined grain structure therein and improved current carrying capability.

Abstract: A method is disclosed for fabricating a wire from niobium tin produced in situ in a filamentous structure capable of achieving the superconducting state which comprises overlapping a tin alloy core comprised of tin-magnesium eutectic alloy with alternating layers of copper and foraminous layers followed by drawing the thus-formed niobium filaments into wire, then heating the wire at sufficiently high temperature to cause the eutectic alloy to homogeneously diffuse through the length of the copper wire and rods to react with the Nb, forming the A-15 crystal structure of Nb.sub.3 Sn, characterized by refined grain structure therein and improved current carrying capability.