Abstract: A method of producing a tape-shaped superconducting wire is provided. The wire maintains a high critical temperature and a high critical current density along the overall length thereof. In this method, raw material powder for the oxide superconductor is first charged in a silver sheath and the sheath charged with the powder is subjected to plastic working to prepare a first flat type wire. On the other hand, a second wire consisting of a tape wire formed by coating a surface of a flat type wire having at least an outer surface consisting essentially of silver or a silver alloy with a metal oxide or ceramics, or a tape wire containing ceramics fibers and a binder dissipated by heat treatment is prepared. The first and second wires are layered with each other, and tightly wound in a pancake coil shape. The wires wound in the pancake coil shape are heat treated for sintering the oxide superconductor. After the heat treatment, the first wire is separated from the second wire.

Abstract: The invention relates to a spray pyrolytic process for the preparation of multi-element metal oxide powders useful as precursors of high temperature superconductor ceramics. Aerosols of aqueous solutions containing corresponding metal salts admixed in the required stoichiometric proportion are sprayed through an independently operated hydrogen/oxygen flame in such a way that a flame temperature of 800.degree.-1100.degree. C. is maintained to form said powders. Any contact of the aerosols and powders generated during the process with carbon or carbon-containing compounds or materials is strictly avoided.

Abstract: A continuous method for manufacturing an elongated superconducting campsite composed of a superconductor consisting of compound oxided and a metal sheath surrounding the superconductor, including the steps of kneading a material powder of superconducting compound oxide with a binder, continuously shaping the resulting kneaded paste into an elongated pre-form by an extruder or by coating technlque, heating the pre-form continuously to remove said binder, wrapping the pre-form with a metallic sheet, and then subjecting the pre-form from wrapped with the metallic sheet to sintering operation to sinter said material powder.

Abstract: The invention relates to a spray pyrolyric process for the preparation of multi-element metal oxide powders useful as precursors of high temperature superconductor ceramics. Aerosols of aqueous solutions containing corresponding metal salts admixed in the required stoichiometric proportion are sprayed through an independently operated hydrogen/oxygen flame in such a way that a flame temperature of 800.degree.-1100.degree. C. is maintained to form said powders. Any contact of the aerosols and powders generated during the process with carbon or carbon-containing compounds or materials is strictly avoided.

Abstract: A process for producing YBCO powders by pyrolysis involves preparing a clear aqueous solution containing the ions yttrium, barium and copper, in the final proportions desired for the powder, in the form of complex compounds, preferably citric complex compounds, and in the presence of a detonating system such as a combination of ammonium ions and nitrate ions. The clear solution is then concentrated by evaporation, until a violent combustion is triggered which is carried out at a high temperature, higher than 250.degree. C. and preferably higher than 850.degree. C.