| 摘要 |
1174498 Super-conductors U HASHIMOTO 26 June 1967 [25 June 1966] 29381/67 Headings H1A A5 and A4D A super-conductor element suitable for use in the windings of a super-conducting magnet is formed by reacting molten gallium at a temperature between 500‹ and 800‹C with the surface of a base material containing at least 50 atomic per cent of vanadium to form a layer of vanadiumgallium alloy containing more gallium than the stoichiometric compound V3Ga, and heating the resulting material at a temperature between 600‹ and 860‹C to form a layer of V 3 Ga between the base material and the gallium-rich layer. One or more of tantalum, zirconium, titanium and biobium may replace part of the vanadium in the base material and the gallium may be partly substituted by at least one of indium, arsenic, antimony, thallium and germanium. The rate of formation of the V 3 Ga layer may be greatly accelerated by coating, e.g. electro-plating, the gallium rich layer with copper or silver prior to the second heat treatment. The effect on the properties of the resulting product of using various treatment temperatures within and outside the ranges specified above is discussed in detail in the Specification. In the embodiments the reaction with molten gallium is effected in a continuous process in an evacuated chamber, the vanadium in wire or ribbon form being passed either through successive vertically arranged crucibles or through a U-shaped crucible containing gallium, and then through a furnace. After being copper or silver plated the resulting wire is heat-treated in a batch or a continuous process. |
