GB497871A - Improvements in or relating to the manufacture of metal articles or masses - Google Patents

Abstract

In a process for making metal masses or articles, for example gear wheels, moulds, engine and machine parts, bombs, carbon dioxide cartridges, and many others, a powder consisting of a normally brittle alloy of iron and carbon, such as white cast iron, is sintered, with or without the application of pressure, the heating being effected in presence of a small proportion of an impurity which is commonly present in the alloy or is added thereto and has a bonding action on the particles during heating. The impurity or addition may be phosphorus, an alloy rich in phosphorus, a copper alloy, arsenic, antimony, or a mixture of copper and tin. In some cases the particles may be oxidized on the surface before or during the heat treatment, and oxides such as magnesia, silica, alumina, or titanium dioxide may also be present. Other elements which may be present include nickel, chromium, titanium, molybdenum, vanadium, silicon, and sulphur. Bodies may be formed having localized areas of one composition embedded in or surrounded by areas of another composition, or they may have embedded in them preformed components.ALSO:In a process for making metal masses or articles, for example gear wheels, moulds, engine and machine parts, bombs, carbon dioxide cartridges, and many others, a powder consisting of a normally brittle alloy of iron and carbon, such as white cast iron, is sintered, with or without the application of pressure, the heating being effected in presence of a small proportion of an impurity which is commonly present in the alloy or is added thereto and has a bonding action on the particles during heating. The impurity or addition may be phosphorus, an alloy rich in phosphorus, a copper alloy, arsenic, antimony, or a mixture of copper and tin. In some cases the particles may be oxidized on the surface before or during the heat treatment, and oxides such as magnesia, silica, alumina, or titanium dioxide may also be present. Other elements which may be present include nickel, chromium, titanium, molybdenum, vanadium, silicon, and sulphur. Bodies may be formed having localized areas of one composition embedded in or surrounded by areas of another composition, or they may have embedded in them preformed components. For example tungsten spheres may be embedded in the nose of bullets or other projectiles made as above. Electric hot plates, electric irons, and other electric heaters may be made by embedding heating elements in powders as above and consolidating.