METHOD OF PREPARING BISMUTH SUPERCONDUCTOR

摘要

Disclosed herein is a method of preparing a bismuth superconductor including the steps of mixing raw materials for formi ? a bismuth superconductor with each other to obtain mixed powder, heat treating the mixed powder, pulverizing the mixed powder and then covering the mixed powder with a metal sheath. The mixed powder covered with the metal sheath is prepared to have a 2223 composition in a composition of Bi-Sr-Ca-Cu or (Bi,Pb)-Sr-Ca-Cu and to contain a superconducting phase which is mainly composed of a 2212 phase, and is pulverized into a mean particle diameter of not more than 1 .mu.m with no conversion of the 2212 phase to an amorphous state.