Preparing Tungsten Carbide Powder from Violet Tungsten Oxide

Violet tungsten oxide with good reducibility and high hydrogen reduction rate is used to prepare ultrafine tungsten powder, so as to obtain high-quality tungsten carbide powder. Carbonization is an extremely important procedure in the preparation process.

Carbonization, refers to the thermal decomposition of solid under the condition of air isolation. During the preparation of tungsten carbide powder, ultrafine tungsten powder is carbonized into tungsten carbide powder. The thorough and complete carbonization, together with high crystal integrity are the guarantees of high-quality tungsten carbide powder. Morever, the sintering of tungsten powder in the carbonization process should be avoided as well, so as to prepare tungsten carbide powder with high quality.

It has been proved that the formation of tungsten carbide powder from tungsten and carbon is different from the general chemical reaction. This process is the diffusion process of carbon at high temperature, which is mixed with tungsten particles. During the diffusion process, in addition to carbon black directly contacted with the surface of tungsten particles, carbon monoxide or hydrocarbon gas will be produced on the surfaces of other carbon black particles. Under the effect of concentration difference, carbon will be continuously decomposed on the surfaces of tungsten particles, providing carbon for the carburizing process.

The carbonization temperature is the most important parameter in the carbonization process. With the increase of carbonization temperature, the carbonization speed is accelerated, and the combined carbon of tungsten carbide powder is increased. Tungsten carbide powder particles with high crystallinity is successfully obtained. However, with the increase of carbonization temperature, the particle size of tungsten carbide powder will also increase and form sintered aggregates. Therefore, how to prepare tungsten carbide powder with high crystallinity and avoid the formation of agglomerates at the same time is the most important issue to be solved during the preparation of tungsten carbide powder.

In addition to carbonization, other preparation procedures also affect the quality of tungsten carbide powder products, the selection of raw material, for example. Only choosing the right raw material, can we obtain high-quality tungsten carbide powder.

Violet tungsten oxide is an ideal material for the production of tungsten carbide powder. It not only has high chemical activity, but has good reducibility and high rate of hydrogen reduction. Ultrafine tungsten powder can be prepared from violet tungsten oxide, so as to obtain high-quality tungsten carbide powder.

• < Prev
• Next >