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Fine grain size violet tungsten oxide can be used to produce ultrafine tungsten powder (W powder) and ultrafine tungsten carbide powder (WC powder). Ultrafine W powder and WC powder prepared by using fine violet tungsten oxide as raw material have better performance. The phase composition of the violet tungsten oxide has a great influence on the properties of the prepared W powder and WC powder. In addition, the content of NH3 in violet tungsten oxide can also greatly affect the…

Nano-needle violet tungsten oxide has a diameter of 20-200nm, a length of 0.5-10μm, and a length-diameter ratio of 5-300. This type of violet tungsten oxide may be synthesized in one step by a solution process. Therefore, the reaction time is short, and the reaction initiation temperature is low. A large quantity of gases are produced in the reaction course, and sufficient contact with air is impeded, so that the generated product, namely, the violet tungsten oxide, is relatively single, favorable…

Violet tungsten oxide nanopowder, compared with blue tungsten oxide nanopowder, is more suitable for the preparation of nano tungsten powder (W powder) and nano tungsten carbide powder (WC powder). That is because the grain size of WC powder prepared by using violet tungsten oxide as raw material is finer although the agglomeration (only weaker agglomeration, which can be eliminated by some means) is more serious. Weaker agglomeration is mainly caused by Van der Waals force and Coulomb forces between particles…

Nano grain size violet tungsten oxide may be produced by APT mild reduction method. The nano violet tungsten oxide prepared by this method has the following advantages: 1. High purity, high crystallinity, and stable thermal performance; 2. Loose powder structure; The shape of grain is mostly spherical and the particle size distribution is even; 3. Large surface area, single pore structure, average particle size up to 26.1 nm, which provides a good prerequisite for the preparation of high-quality tungsten carbide…

High-purity ultrafine violet tungsten oxide, as a new material, is finding wider and wider applications in recent years. Under the same hydrogen reduction process conditions, the grain size of tungsten powder (W powder) prepared by using violet tungsten oxide (VTO) as raw material is finer than that of using blue tungsten oxide (BTO). Therefore, manufacturers who produce ultrafine grain size tungsten carbide powder by using ultrafine tungsten powder as raw material are paying more and more attention to process improvement…

Ultrafine violet tungsten oxide has been used as raw material to replace tungsten acid and yellow tungsten oxide (tungsten trioxide) for the preparation of super fine tungsten powder (W powder) since 1960s. After that, many countries such as the USA, France, Netherlands and Britain, used violet tungsten oxide as raw material to produce W powder. Violet Tungsten Oxide Hydrogen Reduction to Produce Super Fine Tungsten Powder Step one: Weigh 20g violet tungsten oxide; Use 80x50x20 (length x width x height)…

Submicron violet tungsten oxide may be used to prepare submicron tungsten powder (W powder). Cyclic Oxidation-reduction Method to Produce Submicron Tungsten Powder Step one: First reduction of violet tungsten oxide in hydrogen (H2), when temperature reached 860°C, keep it warm for 20min. Step two: Use tungsten powder obtained in step one, slowly heat it to 500°C in air, process the first oxidation when temperature reaches 500°C, and then keep it warm for 10min. Step three: Use sample of step two…

Coarse violet tungsten oxide is mainly a mixture of violet tungsten oxide and blue tungsten oxide. The performance of violet tungsten oxide is significantly affected by the phase composition of violet tungsten oxide. The tungsten oxides are mainly yellow tungsten oxide (tungsten trioxide), blue tungsten oxide, violet tungsten oxide and brown tungsten oxide (tungsten dioxide). In these tungsten oxides, only the violet tungsten oxide is monocrystalline structure, and the other tungsten oxides are polycrystalline structure. So, the powder prepared from…

Fine violet tungsten oxide may be prepared by direct reduction of ammonium paratungstate (APT) under wet hydrogen conditions. The process is short and the equipment is simple. Adopting APT with particle size of 10μm as raw material, under the conditions of pH2O:pH2=1.7:1, the temperature is raised to 1173K in two hours, keeping 1.5h, directly reducing to obtain violet tungsten oxide with particle size of 2.2μm. The grain size of the prepared fine violet tungsten oxide depends on the factors such…

Nano needle-shaped violet tungsten oxide may be applied to produce nano tungsten powder and ultrafine tungsten powder by using Rayleigh instability principle and in-situ hydrogen reduction technology. Violet tungsten oxide is also a dingal nano material with many properties such as photochromicproperty, electrochromicproperty and gasochromicproperty, and it may be used in many kinds of sensors in the future. A Method for Preparing Nano Needle-shaped Violet Tungsten Oxide Raw materials: ammonium paratungstate (APT), or tungstic acid, or tungsten oxide WOx (2≤x≤3).…