As an important intermediate product of transition metal tungsten, tungsten powder (W) is often used to produce tungsten products such as tungsten oxide, tungstate, tungsten carbide, tungsten rod, and tungsten bar due to its strong reducibility. However, due to the different particle shapes of W powder, the physical and chemical properties and specific uses of tungsten products are also different. According to different particle shapes, W powder can be divided into spherical tungsten powder and irregular tungsten powder. The following focuses on the basic information of spherical tungsten powder.
1.Property
The appearance is gray-black fine powder, the melting point is about 3400℃, the boiling point is about 5555℃, the density is 19.3g/cm3 equivalent to gold, the hardness is like diamond, the reducibility is strong, the purity is as high as 99.9%, the loose density is 11.6g/cm3, and it is compact. The density is 12.5g/cm3. Under normal circumstances, the higher the degree of spheroidization of the powder, the smaller the particle size and the narrower the particle size distribution, the better the powder fluidity and the greater the bulk density.
2.Production Method
1) The product can be obtained by using tungsten powder secondary oxidation and reduction technology.
2) Using granulation and sintering method to produce spherical powder.
3) It can be prepared by rotating electrode DC arc plasma method.
4) Prepare large-particle powder from tungsten hexafluoride by vapor deposition method.
5) Use an inductively coupled plasma torch to spheroidize and air-cool the ordinary tungsten powder to obtain the product.
3.Application
Spherical tungsten powder is the main raw material for the production of tungsten alloys, tungsten materials and cemented carbides. W powder mixed with other metal powders can be made into tungsten alloy; W powder can be processed to obtain tungsten materials such as tungsten rods, tungsten wires, tungsten bars; W powder can be made into tungsten carbide powder after carbon treatment, and tungsten carbide powder can be made carbide tools such as milling cutters, drills and molds.
Note: Due to the high melting point and hardness of spherical tungsten powder, it is prone to cracks, deformation, sandwich and other defects during processing, which will affect the properties of the alloy. With the advancement of science and technology, 3D printing technology has gradually replaced the traditional powder metallurgy method, and it is currently an ideal tungsten powder processing technology.
