Patent ID: 6932874

Claim:
A method for producing a superconductor having a high copper to superconductor composition (Cu/SC) ratio by cross-sectional area, comprising in sequence the steps of: (a) preparing by a sequence of operations which include one or more drawing steps, an assembly formed of one or more fine filaments of a NbTi superconductor composition or of Nb as a precursor component for a Nb 3 Sn superconductor alloy composition, which filaments are embedded in a copper-based matrix; and (b) without subjecting said assembly to a prior heating step to diffuse an alloying element into said filaments, electroplating the assembly from step (a) with copper to increase the Cu/filament ratio by cross-sectional area in the resulting product, and thereby increase the said Cu/SC ratio to improve the stability of the final superconductor; and (c) subsequent to step (b) heat diffusing said alloying element into said filaments in the instance where said filaments comprise Nb 3 Sn said superconductor precursor and said matrix includes Sn as said alloying element for said Nb 3 Sn superconductor composition, said heat diffusing being conducted while preventing diffusion of said Sn alloying element into the said electroplated copper by means of a diffusion barrier layer, and wherein when said diffusion to form Nb 3 Sn is carried out said electroplated assembly is in the form of a magnet.