| 摘要 |
<PICT:1001499/C6-C7/1> A coating of superconductive niobium-tin alloy is produced on a chromium-nickel or tungsten wire the surface of which is oxidized or coated with glass, enamel, or ceramic. As shown a vapour-coating apparatus comprises a niobium sphere 9 heated by electron gun 9 and a crucible containing tin which rests in resistance heater 10 which is also provided with a heat radiating screen, a vapour-stream director cylinder and a drip-trap (not shown). Shutters 11 and 12 are provided to control the vapour sources and glow-discharge electrode 11 is provided for cleaning purposes. The wire 4 is arranged on spools 5 and 6 the drive to which may be arranged so that wire 4 is rotated about its axis in addition to moving longitudinally. Wire 4 is first coated with niobium and then with tin, and further alternate layers may be deposited and the final layer of tin is sintered to produce a cohesive surface. The wire may then be mechanically bundled and wound, for example, on to a former after which it is heated, by passing a current through it, to cause the vapour-coated layers to mutually diffuse and form a "hard" superconductive alloy. Other methods of producing members at least partly covered with a superconductive alloy or compound are also described (see Division H1). |
