PROCESS OF MANUFACTURE OF HIGH-TEMPERATURE SUPERCONDUCTIVE ARTICLES FROM POWDER OF SUPERCONDUCTIVE CERAMICS Russian patent published in 1995 - IPC

FIELD: electronics. SUBSTANCE: invention relates to manufacture of articles of any shape and dimensions on basis of high-temperature superconductive ceramics containing oxides of copper and other metals. Process consists in thermal treatment in reducing atmosphere (argon, hydrogen) in compliance with specified mode within temperature region 300- 950 C of starting powder of ceramic carrying elements of IIA, IIIA, IYA, YA groups of periodic system, copper and oxygen. Thermal treatment in argon- hydrogen mixture results in separation of finely dispersed homogeneously distributed metal copper within limits of individual particles of powder. Finely dispersed metal copper homogeneously distributed in particles of powder of produced semifinished item is natural plasticizer. There is no necessity to remote it as it is one of components of high-temperature superconductive ceramic. Presence of such plasticizer makes it possible to use various methods of forming which reveals possibilities to produce compact articles of needed shape and dimensions in shells and without them. Use of copper produced in this process as plasticizer in high-temperature superconductive ceramic excludes harmful effects of carbon as well as of other impurities which are left in samples of high-temperature superconductive ceramic after separation of plasticizers. Compact cermet produced from semifinished item is subjected to thermal treatment in oxidizing atmosphere, for instance, in oxygen which results in synthesis and sintering of high-temperature superconductive ceramic articles of required shapes and dimensions. Proposed process provides for manufacture of conductors from high-temperature superconductive ceramic in metal shell, for example, in silver. For this purpose it is necessary to fill metal shell with powder of starting ceramic before treatment in reducing atmosphere and then conduct thermal treatments in sequence in reducing and oxidizing atmospheres in compliance with specified scheme. If necessary article can be subjected to deformation to give it needed shape and dimensions after treatment in reducing atmosphere and then thermal treatment in oxidizing atmosphere is conducted. EFFECT: enhanced manufacture efficiency. 3 cl