| 摘要 |
1193583 Coating with Nb 3 Sn SIEMENS AG 25 March 1968 [30 March 1967] 14351/68 Headings H1A AS and A4D The super-conductor properties of a layer of Nb 3 Sn formed on a metal or ceramic support by hydrogen reduction of the gaseous halides of Nb and Sn, are improved by cooling the layer in a protective atmosphere of helium, argon, nitrogen or hydrogen from a temperature in the range of 600‹-1000‹C in a time of not less than one minute. The hydrogen content of the layer is reduced to at least 0À5% atom and the Nb 3 Sn layer is preferably formed at 900‹-1000‹C. Instead of the slow cooling, an initially rapidly cooled layer may be heated for at least 30 seconds at 600‹-800‹C and then cooled to 300‹C in a time of not less than one minute. As shown in Fig. 4, a wire or tape 16 of (Registered Trade Mark) "Hastelloy B" is coated in chamber 3 by hydrogen reduction of chlorides of Nb and Sn formed in chlorinators 8 and 10. Heat-treatment is effected in chamber 4 the speed of the tape 16 being adjusted to produce the required coating rate. |
