Tungsten Oxide

The properties of tungsten powder s may be seriously affected by the third element. In production, these characteristics can be used to add third elements to control the particle size of tungsten powder to produce some special kinds of tungsten oxide. This method is called doping. When doped, the tungsten oxide is added to the aqueous solution of the element compound. The most suitable for doping is not yellow tungsten nor purple tungsten, but blue tungsten. The commonly doped elements are sodium, lithium, chromium, and rare earth elements. 1. Sodium-doped: The addition of sodium compounds is a common method in preparing coarse tungsten powders, the amount of sodium is usually between 50-200 and m/g. At 1000°C under wet hydrogen conditions, tungsten powders with an average particle size of 10-25 um can be obtained according to the thickness of the material layer, high temperature ensures strong volatilization of sodium at the end of the reduction process, it is ...

In the production of tungsten metal by powder metallurgy, the chemical purity is especially important because the subsequent sintering process can only be achieved by evaporation to a certain extent. With the development of industry, the requirement of the purity of tungsten powder is increasing day by day, because the impurities left after the sintering of tungsten powder have a great influence on the processability and properties of the final products. In the production process of tungsten concentrate to tungsten powder, tungsten purity is constantly improved, and the purity is high when APT is made. However, when APT is processed into tungsten powder, the purity decreases. Why? According to the study, tungsten powder impurities mainly from the material and the reduction of the furnace tube and metal boat contact, as a result, the impurity content is increased, and these impurities are present in a heterogeneous form, the result is the increase in impurity conte...