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Process research on particle size characteristics of reduced tungsten powder |
CHEN Shanshan |
Xiamen Golden Egret Special Alloy Co., Ltd., Xiamen 361000, China |
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Abstract The particle size, particle size distribution and agglomeration of tungsten powder are closely related to the properties of subsequent products. In this paper, the reduction process of yellow tungsten oxide and blue tungsten oxide is studied by static reduction test at different temperature and time. The particle size distribution and agglomeration state of the powder were analyzed by scanning electron microscope, the phase change process of the powder was analyzed by X-ray diffraction and oxygen index, and the macroscopic particle size change was characterized by specific surface area. The results show that yellow tungsten (WO3) and blue tungsten (WO2.9) have the same reaction rate and morphology change process. The particle size, particle size distribution and agglomeration are closely related to reduction temperature. After reduction at a low temperature below 700 ℃, the tungsten powder particles are uniform in size and easy to agglomerate. When the temperature is above 800 ℃, the agglomeration of the powder decreases and the particle size is uneven.
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Received: 20 December 2019
Published: 18 January 2021
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