6 Ways to Make Metal Tungsten Powder
Posted on April 13, 2020 by aemmetal
Tungsten powder is the main raw material for processing P / M tungsten products and tungsten alloys. Pure tungsten powder can be made into wire, rod, tube, plate and other processing materials and certain shape products. Tungsten powder
can be mixed with other metal powder to make various tungsten alloys. More than 70% of tungsten powder is used in cemented carbide production. At present, the main methods of producing tungsten powder are as follows:
1. Hydrogen reduction of tungsten oxide
That is, using H2 as reducing agent to reduce tungsten oxide to tungsten powder. Taking the reduction of WO₃hydrogen as an example, the total reaction is as follows:
At present, tungsten oxides used as raw materials for hydrogen reduction are mainly yellow tungsten oxide (WO3
), blue tungsten oxide (mainly WO2.9) and purple tungsten oxide (WO2.72). The hydrogen reduction of tungsten oxide is the main method to produce tungsten powder.
2. Hydrogen reduction of tungsten halide
That is to say, the method of reducing tungsten halides (such as tungsten chloride and tungsten fluoride) to tungsten metal by using H2 as reducing agent. For example, for the hydrogen reduction of WCl6, the total reaction is as follows:
The hydrogen reduction process of tungsten halide is gas-phase reaction, which is mainly used in the preparation of ultrafine tungsten powder or tungsten coating by chemical vapor deposition. At present, the chloride reduction method of tungsten halide is only used in small-scale production.
3. Tungsten oxide carbon reduction method
When the mixture of tungsten oxide and carbon is heated to a certain temperature, tungsten oxide is reduced to tungsten powder. Taking the reduction of WO3
carbon as an example, the total reaction is as follows:
Sometimes a small amount of hydrogen is introduced into the furnace to promote the carbon reduction process. Due to the high carbon content of tungsten powder towel made by this method, it is not suitable for tungsten products. At present, the technology of producing tungsten powder by carbon reduction method is less, but it is used more and more in the direct production of tungsten carbide, especially ultrafine tungsten carbide powder and tungsten carbide composite powder.
4. Molten salt electrolysis
5. Zn reduction
6. Plasma hydrogen reduction
The last three methods are not going to be explained here. Interested friends can contact us directly for consultation.