Process for producing high temperature superconductor and shaped product thereof.

摘要

A high-temperature superconductor of the composition Bi2(Sr,Ca)3Cu2O8+x having a strontium:calcium ratio of from 5:1 to 2:1 and a value for x of between 0 and 2 is prepared by vigorously mixing the oxides and/or carbonates of bismuth, strontium, calcium and copper in a stoichiometric ratio. The mixture is heated at temperatures of from 870 to 1100 DEG C until a homogeneous melt is formed. The melt is cast in chill moulds and allowed to solidify therein. The castings removed from the moulds are conditioned at 780 to 850 DEG C for from 6 to 30 hours. The conditioned castings are finally treated for 6 hours at a temperature of from 600 to 820 DEG C in an oxygen atmosphere.
The castings can be converted into mouldings of any desired dimensions by mechanical methods before conditioning.
The shape and dimensions of the mouldings can also be determined through the shape and dimensions of the mould used in the production of the castings.