Doped ammonium metatungstate (AMT) generally refers to the incorporation of other substance of ammonium metatungstate in liquid phase for preparing special features tungsten material. Such as the potassium-doped ammonium metatungstate for preparing potassium-doped tungsten powder, thus can be used for the preparation of tungsten filament lamp; arsenic-doped AMT for preparing arsenic-doped tungsten powder.

A study has taken the arsenic doping ammonium metatungstate to prepare nano tungsten powder, in which ammonium metatungstate added to the solution of nitric acid elemental arsenic, the content of the feedstock arsenic 0.1~5wt%; stir, bake dry, after the precursor abrasive composite powder prepared by arsenic doping; precursor composite powder doped with arsenic placed in box-type resistance furnace in an air atmosphere 580~620 ℃ roasting, heat 2~3h, prepared yellow ferric tungsten oxide powder; yellow tungsten trioxide powder was put into a tube furnace atmosphere, under a hydrogen reduction, 5℃/min heating, the reduction temperature 780~820 ℃, heat 3~4h, prepared nano tungsten powder.