Patent ID: 7134181

Claim:
A method for producing a superfine multi-core Nb 3 Al superconductive wire comprising the process of, (A) coating a Nb 3 Al superconductive wire with Cu or Ag as the stabilizing material; then (B) subjecting the Nb 3 Al superconductive wire to a hot isostatic press (HIP) process for 10 minutes or more in a inert gas environment with a pressure of 40 atmospheres or more; and then (C) subjecting the Nb 3 Al superconductive wire to heat treatment for 1–200 hours in temperature range of 680–850° C., wherein the Nb 3 Al superconductive wire is obtained by subjecting a precursor wire having a superfine multi-core structure in which a plurality of Nb/Al complex cores are embedded in Nb, Ta, a Nb based dilute alloy, or a Ta based dilute alloy as the matrix to a rapid heating and quenching treatment comprising rapidly heating to a temperature range near 2,000° C. in 2 seconds.