| 摘要 |
1,135,015. Coating with aluminium. SOC. NATIONALE D'ETUDE ET DE CONSTRUCTION DE MOTEURS D'AVIATION. Feb. 10, 1966 [Feb.16, 1965], No.5889/66. Heading C7F. In a process of depositing Al on a refractory metal alloy, such as alloys based on Ni or Co containing Cr, W, Fe and Mo, a gaseous Al halide is formed by reaction between an Al alloy and a halogen, said alloy remaining in the solid state at the reaction temperature, and the gaseous halide is then contacted with the heated refractory alloy to deposit Al. The donor Al alloy preferably contains 6-50% Al and is based on Co, Ni, Cr or Fe i.e. one of the metals contained in the refractory alloy which is to be coated. As shown in Fig.1 refractory alloy parts 4 are suspended in a reaction chamber 1 and the donor Al alloy 6 as a powder or in lump form is separated from the donor 6 by a perforated wall 7. A halogen either as F and/or Cl or a compound is introduced into the reaction chamber which is then heated to 950‹ -1200‹C. in argon, hydrogen on cracked ammonia, the amount of halogen introduced amounting to 0À1 - 1% by weight of the donor 6. Heating is continued for 1-5 hours and the coating thickness is 0À025-0À1mm. In a separate embodiment Fig.2 (not shown) the donor material 6 is located in a separate chamber and the halide gas formed, which may be diluted with argon, is passed over the heated refractory alloy in a second chamber. |
