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Single-crystal ammonium paratungstate has properties of good fluidity, high bulk density, small and uniform grain gaps in the blank, few mechanical defects and high compaction density. It also has excellent physical properties such as good compression resistance, tensile resistance, impact resistance, shear resistance and fracture strength. Therefore, single-crystal ammonium paratungstate is an ideal raw material for the production of high-performance tungsten materials such as tungsten powder, tungsten wire, tungsten carbide microdrill, tungsten carbide tool, and tungsten alloy ammunition. More details,…

Spherical ultrafine ammonium paratungstate, or spherical single crystal ultrafine ammonium paratungstate (APT), is the key powder material for fabricating high-density alloys with high performance. More specifically, the spherical ultrafine APT is calcined to obtain tungsten oxide, and spherical tungsten powder is prepared after hydrogen reduction of tungsten oxide. The prepared spherical W powder has the advantages of high bulk density, good fluidity and easy filling of film cavity. Also, it makes the compact have uniform density. So it can be…

Coarse crystalized ammonium paratungstate (APT) is a flaky or needle-like white crystal that is slightly soluble in water and insoluble in alcohol. As a raw material for the powder metallurgy industry, coarse crystalized APT has the characteristics of simple production process, high purity, high bulk density, good fluidity, and easy storage and transportation. More details, please visit: http://ammonium-paratungstate.com/index.html The particle size of ammonium paratungstate crystals has a great influence on the particle size of subsequent tungsten powders. It has been…

Ammonium paratungstate tetrahydrate, or APT·4H2O, is an important intermediate product in the production of tungsten powder. It has been reported that it is a key process to crystallize APT·4H2O from an aqueous solution of ammonium tungstate in the current preparation method of tungsten powder. More details, please visit: http://ammonium-paratungstate.com/index.html According to the literatures, ammonium paratungstate tetrahydrate is an intermediate for the production of metal tungsten, tungsten-containing catalysts or hard materials based on tungsten (such as tungsten carbide) or sputtering targets.…

Ultrafine ammonium paratungstate is an important raw material for the production of nano tungsten powder. Since the 1990s, nano tungsten powder has been generally concerned by researchers all over the world, and ultrafine APT, as an important raw material for preparation of W powder, is also receiving much attention. More details, please visit: http://ammonium-paratungstate.com/index.html However, the particle size of common ammonium paratungstate is 25-45 μm, which is difficult to meet the requirements of producing nano tungsten powder, so the preparation…

Chromium doped ammonium paratungstate may be produced by doping chromium (Cr) in evaporation crystallization process during the production of ammonium paratungstate. Adopting chromium acetate (CH3COO)3Cr (analytical reagent) and ammonium tungstate solution obtained by dissolving high-purity WO3 with ammonia water as raw materials to study the process of preparing APT powder by adding chromium acetate during crystallization. The result showed that: 1. Chromium mainly precipitated in the precipitation form of Cr(OH)3, which is prior to ammonium paratungstate, and the pH value…

Arsenic doped ammonium paratungstate may be prepared by adopting simple arsenic, nitric acid solution and ammonium paratungstate (APT) as raw materials and forming in liquid phase, the preparing steps are as below: 1. Dissolve a certain amount of simple arsenic (As) in the nitric acid solution with a certain concentration until it completely dissolves; 2. Add APT powder into the nitric acid solution of simple arsenic, and control the content of arsenic in a certain value; 3. After completely mixing…

Sodium doped ammonium paratungstate may be used to prepare coarse grain size tungsten trioxide (WO3), and the content of sodium (Na) may affect the particle size of tungsten (W) powder prepared by WO3. APT with high sodium content may be calcined to produce high sodium content of WO3 powder – an upstream raw material for preparing coarse grain size tungsten powder, which is a raw material for tungsten carbide with coarse grain size. And tungsten carbide with coarse grain size…

Coarse ammonium paratungstate has advantages of large apparent density and good fluidity, and its demand increases year by year as customers are requiring more and more strictly on the performance of subsequent products now. Preparation of Coarse Ammonium Paratungstate 1. Experimental solution and equipment: (1) Adopt (NH4)2WO4 solutions produced by classical process and ion exchange process as test material liquid; Part of the solution was prepared by diluting ammonia water. (2) A 1500L open type enamel reactor equipped with an…

Super grade ammonium paratungstate is ammonium paratungstate with grade of APT-0, which is divided by national standard. Generally, traditional process to prepare high-purity ammonium paratungstate is first to dissolve super grade ammonium paratungstate by ammonia-dissolving method, and then evaporation recrystallization. The high-purity APT produced by traditional process has the disadvantages as follows: The energy consumption is high and the comprehensive recovery rate of resources is low. Also, equipment and investment are increased when compared with new processing technology, so that…