Abstract
Owing to its high production costs, complexity of equipment, and difficulty in controlling parameters, spherical or subglobose tungsten powder preparation method cannot meet the demand of industrial production. Tungstic oxide powder was treated by particle composite system and its effects were studied. Morphologies of particles were investigated by scanning electron microscopy (SEM). Particle size analysis was carried out and the related mechanism was discussed. The results show that the processing effect is best when the rotational speed is set at 4,000 r·min−1 for 15 min: the powder particles become nearly spherical and their sharp edge angles are rounded off and reshaped. When the processing time is 60 min, the powders smash to pieces because of too much energy inputting. So the test results, such as grain size distribution, can be explained well. Nearly spherical tungsten powder is obtained after reduction at 780 °C for 2 h and its flow ability is significantly improved.
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This study was financially supported by the International Science and Technology Cooperation Program of China (No. 2010DFR50360).
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Wang, CC., Jia, CC., Gao, P. et al. Spherical modification of tungsten oxide powder and its mechanism analysis. Rare Met. 34, 183–188 (2015). https://doi.org/10.1007/s12598-014-0370-8
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DOI: https://doi.org/10.1007/s12598-014-0370-8