| 摘要 |
<p>1494176 Superconductors; Nb 3 GeUNITED STATES ENERGY RESEARCH & DEVELOPMENT ADMINISTRATION 24 May 1976 [26 June 1975] 21364/76 Heading CIA [Also in Division C7] The invention relates to the superconductor composition Nb 3 Ge containing 1 to 10 at. per cent oxygen and having a critical temperature of at least 20 K. An article displaying superconductive properties is prepared by coating a metal substrate, preferably copper, steel or stainless steel, with the superconductor composition. In the Figure, in process 21, an admixture 25 of NbCl 5 and NbOCl 3 powder is entrained in an inert (e.g. Ar) gas flow and passes into the vaporizer 4. Alternatively, in process 20 Nb metal in the form of strips or cuttings at 250-260‹ C. is chlorinated in 3 by passing an Ar flow I and Cl 2 flow 2 mixed in a volume ratio of about 4:1 therethrough; a small addition of water vapour is added to the NbCl 5 vapour so produced to yield, in part, NbOCl 3 . The resulting Nb containing gas stream is admixed with an Ar/H 2 and Ar/GeCl 4 vapour mixture at 11 and the chlorides are reduced in the coating chamber 12 to yield coatings of Nb 3 Ge containing the required amount of O 2 on suitable substrates.</p> |
