Processing of oxide superconductors

摘要

A method for preparing a BSCCO-2223 oxide superconducting article includes annealing an oxide superconductor article comprised of BSCCO-2223 oxide superconductor at a temperature selected from the range of about 500° C.<=T<=787° C. and an annealing atmosphere having an oxygen pressure selected from within the region having a lower bound defined by the equation, PO2(lower)>=3.5x1010exp(-32,000/T+273) and an upper bound defined by the equation, PO2(upper)<=1.1x1012exp(-32,000/T+273). The article is annealed for a time sufficient to provide at least a 10% increase in critical current density as compared to the critical current density of the pre-anneal oxide superconductor article. An oxide superconductor having the formula Bi2-yPbySr2Ca2Cu3O10+x, where 0<=x<=1.5 and where 0<=y<=0.6 is obtained, the oxide superconductor characterized by a critical transition temperature of greater than 111.0 K, as determined by four point probe method.