| 摘要 |
1,214,354. Coating with boron. UNITED AIRCRAFT CORP. 15 Feb., 1968 [24 Feb., 1967], No. 7449/68. Heading C1A. [Also in Division C7] Boron is deposited on a resistively heated wire of, e.g. W, Ta, Mo, Al, Al coated W, W coated Si or glass-coated copper, by decomposition of boron trichloride mixed with hydrogen. The wire 38 is fed through two stages of a quartz or heat resistant glass reaction chamber. In the second stage the hydrogen and boron trichloride are fed through pipes 10, 12 and 14, 16 to give concurrent and counter-current gas flow. The effluent gas, which is a mixture of the unreacted gas and hydrogen chloride, is extracted through a pipe 18 and fed to the first chamber. The concentration of boron halide admitted to the second stage is so adjusted that peak temperatures are obtained in both the concurrent and countercurrent regions of the second chamber. Each chamber has conductive, liquid seals 36 of, e.g. mercury. |
