Fabrication of ultrafine tungsten-based alloy powders by novel soda reduction process

Abstract

A novel reduction method has been developed to fabricate ultrafine tungsten heavy alloy powders, with ammonium metatungstate (AMT), iron(II) chloride tetrahydrate (FeCl 2·4H 2O), nickel(II) chloride hexahydrate (NiCl 2·6H 2O) as source materials and sodium tungstate dihydrate (Na 2WO 4·2H 2O) as a reductant. In the preparation of mixtures the amounts of the source components were chosen so as to obtain alloy of 93W–5Ni–2Fe composition (wt.%). The obtained powders were characterized by X-ray diffraction, XPS, field-emission scanning microscope (FESEM), and chemical composition was analyzed by EDX.