Tungsten Powder Producing Method
Tungsten powder preparation method of hydrogen and carbon reduction, these two methods are the early tungsten powder preparation method. Its principle is to reduce raw material of tungsten trioxide (WO3) or ammonium paratungstate (APT) in a reducing atmosphere (hydrogen or carbon) to tungsten powder. While, the tungsten oxide carbon reduction method is the earlier method for preparing tungsten powder with the reduction temperature up to 1050°C and lower purity of the obtained tungsten powder.
Some new methods for preparing tungsten powder are high-energy ball milling, gas evaporation, plasma, SHS reduction, molten salt electrolysis, tungsten oxide powder reduction method ect., these methods are suitable for preparing nano tungsten powder, and exhibits good prospects for development.
Energy ball milling method is by rotating or vibrating to make hard ball to strongly hit, grain and mix the raw material, which can significantly reduce the activation energy, refining grains, enhancing powder’s activity, increasing sintering ability, and induce low-temperature chemical reaction, thus finally crush the metal or alloy powder into the nanoscale particles.
澳门老永利总部Gas evaporation method is usually used for the dry production of nano-powder, with the principle of the supersaturation concentration of metal vapor in the absence of refrigerant and crystal nucleation carrier gas (such as argon, nitrogen).
澳门老永利总部Self-propagating high-temperature synthesis (SHS) is a method for producing inorganic compounds by exothermic reactions, usually involving salts or pure metals. A variant of this method is known as solid state metathesis (SSM). Since the process occurs at high temperatures, the method is ideally suited for the production of refractory materials with unusual properties, for example: powders, metallic alloys, or ceramics with high purity, corrosion–resistance at high–temperature or super-hardnessity.