| 摘要 |
1,150,356. Platinum group metal and gold coating alloys, molybdenum and tungsten alloys. INTERNATIONAL NICKEL Ltd. Oct. 20, 1966 [Oct. 26, 1965], No. 45306/65. Headings C7A and C7F. An article for use at a given elevated temperature is formed from a body of Ir, Ru, Mo, W, or an alloy thereof with Au, Pd, Pt, Au and Pd, or Au and Pt, with or without up to 5% of other metals such as Zr and/or Ti (with Ir) or Rh (with Ru), protected from oxidation by an oxidation-resistant coating of an alloy of Au and Pd, or Au and Pt, with or without Ir, Ru, Mo or W, the composition of which is determined at the end P of a tie-line Z (the other end N being the body composition) drawn on a ternary equilibrium diagram for the given temperature, the axis representing Ir/Ru/Mo/W, Au and Pd/Pt respectively. The compositions of the coating and body may lie within radii of 5% change in composition of the ends P, N of a tieline Z. The coating alloy is preferably prepared initially by vacuum melting or powder metallurgy. The coating may be applied in the form of sheet to a sheet body, or a sleeve to a wire body, and bonded to the body by rolling or hot-wire drawing. For bodies of complex shape, the coating may be applied by electro-positioning the various metals independently and fusing, or by hot dipping, metal or plasma arc spraying, or the flake powder technique. Examples of coating alloys Ru-Au-Pd, Ir-Au-Pd, Au-Pt, Mo-Au-Pd and W-Au-Pd, and body alloys Ir-Pd, Ru-Pt, Ru-Au-Pt, Ir-Au-Pt, Pd-Ru, Pt-Ir, Mo-Pd, W-Pd and W-Au-Pt are specified. |
