METHOD FOR PRODUCING oxide superconductor and a bismuth-based superconducting wire

摘要

This invention provides a process for producing a bismuth-based oxide superconductor, which can provide a high critical current density, and a superconductive wire comprising the bismuth-based oxide superconductor produced by the process. The production process is a process for producing a 2223 phase-containing bismuth-based oxide superconductor having a 2223 composition in a composition of Bi-Sr-Ca-Cu or (Bi,Pb)-Sr-Ca-Cu and comprises a first step of filling a starting material containing a 2212 phase having a critical temperature of 70 K or below and having a 2212 composition in a composition of Bi-Sr-Ca-Cu or (Bi,Pb)-Sr-Ca-Cu into a metal sheath, a second step of subjecting the metal sheath filled with the starting material to plastic working, and a third step of heat treating the metal sheath filled with the starting material.