The invention belongs to the technical field of
tungsten smelting and production and in particular relates to a method for preparing uniformly
chromium-doped APT (
ammonium paratungstate). The method for preparing the uniformly
chromium doped APT comprises the following steps: (1) dissolving WO3 with
ammonia; (2) adding soluble
chromic salt, heating, and carrying out
evaporation crystallization; (3) after liquid in a crystallizing pan is completely boiled, stopping steam introduction while stirring continuously; (4) when
crystal nucleuses appear in the crystallizing pan, regulating a rotating speed, and maintaining a
steam pressure; (5) when density of a solution reaches 1.1g / cm<3>, controlling a stirring speed, and maintaining the
steam pressure; and (6) when the pH of the solution is 6.7-7.0, stopping heating, cooling and emptying. The method for preparing the uniformly
chromium doped APT has the beneficial effects that APT
powder with chromium uniformly distributed can be prepared, chromium is uniformly distributed at each APT
crystal boundary, and molecular scale mixing is realized; and the prepared chromium doped APT can be used for effectively inhibiting abnormal growth of WC
crystal grains in a
liquid phase sintering process, so that properties of a hard
alloy are greatly improved.