Effects of Mechanical Activation during the Synthesis of Tungsten Carbide Powders by Carbothermic Reduction of Tungsten Oxide

Abstract:

In this work, the effects of mechanical milling on the extent of reduction were investigated to give an overview of potential improvements in the preparation of WC. A mixture of graphite and tungsten oxide (WO3) was mechanically milled together for 10 h. The as-milled powder and un-milled powder were investigated by thermal analysis, isothermal treatment, and X-ray diffraction to determine the effect of milling on the carbothermal reduction of WO3 to tungsten carbide (WC). The as-milled powder underwent a rapid reduction reaction at about 150°C lower than the un-milled powder. The reduction sequence to WC was illustrated to differ for the two powders. The milled powder showed complete reduction to WC in 1 h at 1215°C whereas the un-milled powder was incompletely reduced. Finally, WC powder was readily achieved by carbothermic reduction of mechanical activated WO3 and graphite, leaving its grains nano-sized.

• Periodical: Defect and Diffusion Forum (Volumes 312-315)
• Pages: 248-252
• DOI: https://doi.org/10.4028/www.scientific.net/DDF.312-315.248
• Online since: April 2011
• Authors: J. Ma, Shi Gen Zhu, H. Ding, W.S. Gu
• Keywords: Ball Milling, Mechanical Alloying (MA), Solid State Synthesis, Tungsten Carbide

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