Large quantities of tungsten heavy metal scrap are produced as a result of. milling and turning operations used to bring sintered and/or sintered and thermo-mechanically treated materials to their final net shape. Two general methods have been applied for recycling the tungsten from this scrap material, an oxidation-reduction process in which the matrix elements such as iron and nickel remain in the final powder product to a large extent and a chemical process which can produce tungsten powder which is indistinguishable from virgin material. Chemically recycled tungsten powder prepared from scrap heavy metal was evaluated as a substitute for virgin tungsten powder in the production of heavy metal materials for applications such as radiation shielding. The recycling process was adapted to produce material which, when substituted for non-recycled powder, did not significantly affect the quality of the sintered and heat treated metal product.
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