GB370566A - Improvements in or relating to hard metal alloys - Google Patents

Abstract

A hard alloy for tools, implements and projectiles consists of 38-98 per cent of tungsten, 2-9,5 per cent of beryllium, with or without up to 3 per cent of carbon and 0-57 per cent of iron, the content of beryllium being at least 5 per cent if the tungsten is less than 82 per cent, and the content of iron at least 5 per cent if the carbon exceeds 2 per cent. The tungsten may be replaced wholly or in part by molybdenum and chromium, the iron wholly or in part by nickel, cobalt, manganese, or titanium, and the carbon in part by other hardening agents such as aluminium, magnesium, silicon, boron, zirconium, cerium. The alloy may be produced by sintering or heating and casting in a hydrogen atmosphere or in vacuum and the constituents may be present in the starting material as elements or alloys. In particular the beryllides and if desired also the carbides of tungsten, molybdenum, and chromium may be produced in a separate melting or sintering process, then ground and added to the other constituents comprising the tough metals, alloyed if desired, the hardening elements, and if necessary additional amounts of tungsten, molybdenum, and chromium. The Specification as open to inspection under Sect. 91 (3) (a) includes also alloys in which the beryllium is in part replaced by other hardening agents such as aluminium, magnesium, silicon, boron, zirconium, &c. This subject-matter does not appear in the Specification as accepted.