Patent ID: 6536096
Filing Date: 2003-03-25
Classification: C04B,H01L,Y10T

Abstract:
A method of preparing a bismuth oxide superconducting wire, comprising the steps of:preparing powder of not more than 1 &mgr;m in mean particle diameter containing a mixture of superconducting phases composed of 2212 phases and 2223 phases within said 2212 phases, and non-superconducting phases obtained by calcining and pulverizing raw material powder at least once; degassing said powder by heat treating said powder at a high temperature in a decompressed atmosphere; covering said powder with a metal thereby forming a composite; preparing a round wire by deformation-processing the composite of said powder covered with said metal; deformation-processing said round wire into a tape type or flat type wire; heat treating said wire, thereby transforming said 2212 phases contained in said superconducting phases to 2223 phases, and thereby grain-growing said 2223 phases; densifying said 2223 phases; and bonding said 2223 phases with each other and dispersing said non-superconducting phases by performing a heat treatment.