Arsenic doped ammonium paratungstate (APT) is excellent raw material of nano tungsten powder, since the particle size and distribution of tungsten based alloy is directly inherited from tungsten powder, while the preparation of high quality nano-crystalline WC powder is the key technology for preparing nano-crystalline WC-Co cemented carbide. Therefore, the preparation of nanometer tungsten powder with good dispersion and uniform particle size distribution has become the key to the production of nano-crystalline WC-Co cemented carbide.

The preparation of arsenic doped ammonium paratungstate (APT) is taking simple arsenic and nitric acid solution, ammonium paratungstate as raw materials and forming in liquid phase, the preparing steps are as follow:
1. Dissolve a certain amount of simple arsenic (As) in the nitric acid solution with a certain concentration to completely dissolve;
2. Add ammonium paratungstate into the nitric acid solution of simple arsenic, and control the content of arsenic in a certain value;
3. After completely mixing by electric stirring, the raw material is dried in an oven under 70~90°C for 8~10 hours, and finally get the arsenic doped ammonium paratungstate after grinding.