| 摘要 |
A hard alloy suitable for tools and tool parts contains 75-97 per cent of aluminium carbide, the remainder being a metal or metals, e.g., copper, cobalt, iron, nickel, or chromium. Calcium, molybdenum, or aluminium may be present as additional metals. The aluminium carbide may be partly replaced by the carbides of tungsten, molybdenum, titanium, manganese, tantalum, vanadium, zirconium, or silicon. The Specification as open to inspection under Sect. 91 comprises also alloys containing carbides, about 0.5-2 per cent of light metals such as aluminium or calcium, and about 3-25 per cent of iron, cobalt, nickel, chromium, &c., as auxiliary metals; a method of making hard alloys by pressing a moulded mixture containing carbides and auxiliary metals, and regulating the pressure during heating and cooling particularly in the critical temperature range in which the material dilates or contracts suddenly; and a method of making tools by combining a hard alloy working portion with a carrier, heating the whole tool, or the working portion only, to or above the critical temperature of the hard alloy, and cooling continuously or stepwise. This subject-matter does not appear in the Specification as accepted; the latter method of making tools, however, forms the subject of Specification 406,289. |
