Influence of Ball-milling on Sintered Body Density of Fine Tungsten Powder

Hydrogen is widely used to prepare tungsten from tungsten oxides. Such a gas is combustible and strict measures must be taken. However, assisted by Mg or Li3N, tungsten can be prepared through the ball milling at room temperature. The reduction of WO3by Al powder is investigated thermodynamically. Simulations on the loss of Gibbs energy of these hypothetic reactions reveal that the reduction of WO3and WO2(OH)2(or H2WO4) is feasible when Al powder is used; and it is more difficult to generate the intermediate tungsten oxides such as WO2, WO2.72and WO2.9. In addition, it is better to prepare tungsten powder in vacuum containers in view of economy.

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Production of Fine Tungsten Powder by Electrolytic Reduction of Solid CaWO4in Molten Salt

Journal of The Electrochemical Society ◽

10.1149/2.113206jes ◽

2012 ◽

Vol 159 (6) ◽

pp. E139-E143 ◽

Cited By ~ 14

Author(s):

Dingding Tang ◽

Wei Xiao ◽

Huayi Yin ◽

Longfei Tian ◽

Dihua Wang

Keyword(s):

Molten Salt ◽

Tungsten Powder ◽

Electrolytic Reduction ◽

Fine Tungsten

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Effect of Ball Milling Parameters on the Refinement of Tungsten Powder

Metals ◽

10.3390/met8040281 ◽

2018 ◽

Vol 8 (4) ◽

pp. 281 ◽

Cited By ~ 2

Author(s):

Zaoming Wu ◽

Yanxia Liang ◽

Engang Fu ◽

Jinlong Du ◽

Peipei Wang ◽

...

Keyword(s):

Ball Milling ◽

Tungsten Powder ◽

Milling Parameters

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Refinement process and mechanisms of tungsten powder by high energy ball milling

International Journal of Refractory Metals and Hard Materials ◽

10.1016/j.ijrmhm.2017.04.006 ◽

2017 ◽

Vol 67 ◽

pp. 1-8 ◽

Cited By ~ 18

Author(s):

Y.X. Liang ◽

Z.M. Wu ◽

E.G. Fu ◽

J.L. Du ◽

P.P. Wang ◽

...

Keyword(s):

Ball Milling ◽

Tungsten Powder ◽

High Energy ◽

High Energy Ball Milling ◽

Energy Ball ◽

Refinement Process

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Investigation of X-ray radiation effect on the structure and microhardness of tungsten powder filled composite

Izvestiya Vuzov Poroshkovaya Metallurgiya i Funktsional’nye Pokrytiya (Universitiesʹ Proceedings Powder Metallurgy аnd Functional Coatings) ◽

10.17073/1997-308x-2018-3-87-92 ◽

2018 ◽

pp. 87-92

Author(s):

A. A. Lozovan ◽

F. E. Vilkov

Keyword(s):

Radiation Resistance ◽

Tungsten Powder ◽

Absorbed Dose ◽

Test Material ◽

Simultaneous Increase ◽

X Ray ◽

Local Stresses ◽

Before And After ◽

Fine Tungsten ◽

High Degree

The study focuses on the radiation resistance of a composite filled with fine tungsten powder having the 200–500 nm particle size. The studied composite is designed to provide radiation protection of electronic equipment. A sample with the test material was exposed to continuous spectrum X-ray radiation to an absorbed dose of 3 MGy. A characteristic of radiation resistance was sample microhardness measured before and after X-ray irradiation. Scanning electron microscopy was used to study the microstructure of a sample transverse cleavage after irradiation, and it was found that the sample had no visible defects in its structure. This result can be explained by uniform energy dispersion from local stresses due to high degree of composite filling with tungsten powder having a high thermal conductivity coefficient. The study of sample microhardness showed its 10 % increase attributable to the radiation hardening effect where increasing strength results in a simultaneous increase in microhardness. Experiments proved that this effect is manifested with an increase in the absorbed radiation dose.

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Fine Spherical Tungsten Powder Prepared by Precipitation Reaction

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.117-119.967 ◽

2011 ◽

Vol 117-119 ◽

pp. 967-970

Author(s):

Tao Lin ◽

Yan Jun Li ◽

Cheng Yi Wu ◽

Zhi Meng Guo

Keyword(s):

Particle Size ◽

Tungsten Powder ◽

Sodium Dodecyl ◽

Precipitation Reaction ◽

Mechanical Agitation ◽

Ammonium Tungstate ◽

Fine Tungsten ◽

Strong Acids ◽

Addition Amount ◽

Uniform Particle Size

The spherical tungsten powder was prepared by chemical reaction with ammonium tungstate and strong acids under ultrasonic and mechanical agitation. After precipitation reaction, the precipitate was dried and grinded, and then reduced into tungsten powder with hydrogen. The effects of acid kinds and dispersant on the fine tungsten powder were studied in this paper. The result shows that the acid kinds and its addition amount have great effect on the shape of tungsten particles. The tungsten powder with uniform particle size and spherical could be prepared by adding 17ml sulfric acid into 100ml ammonium tungstate. The tungsten particles can be finer and more dispersive, and have a spherical with addition of dispersant SDS (Sodium dodecyl sulfate). The particle size is about 1.5 micrometer.

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