Superconductor technology: apparatus – material – process – High temperature – per se – Having tc greater than or equal to 150 k
Patent
1988-10-24
1991-02-26
Roy, Upendra
Superconductor technology: apparatus, material, process
High temperature , per se
Having tc greater than or equal to 150 k
420901, 156610, 252521, 423593, 423594, 505737, C01F 1700, H01L 3912
Patent
active
049961896
ABSTRACT:
A novel method of producing mixed metal oxide powder (e.g., ferrite powder, or high temperature superconductor powder such as YBa.sub.2 Cu.sub.3 O.sub.x powder) is disclosed. The method comprises forming an intimate mixture of appropriate metal salts (e.g., nitrates and acetates), at least one of which is an oxidizing agent with respect to at least one of the others, and heating the mixture to a reaction temperature such that an exothermic redox reaction occurs. Appropriate choice of oxidizing and reducing agents permits control of heat of reaction and reaction temperature. The product of the reaction typically is a precursor of the desired mixed oxide, the precursor typically consisting essentially of the metal constituents of the mixed oxide and oxygen. Heat treatment in an O.sub.2 -containing atmosphere transforms the precursor into the desired mixed oxide powder. The thus produced powder can then be used in conventional fashion, e.g., to produce bodies therefrom by pressing and/or sintering.
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Kourtakis Kostantinos
Robbins Murray
AT&T Bell Laboratories
Pacher Eugen E.
Roy Upendra
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