Abstract
Nanocrystalline cubic substoichiometric WC1 − z powders were synthesized by a mechanochemical method at room temperature, a process of highly reactive energetic ball milling of WO3 + 3Mg mixtures containing excessive graphite as a source of carbon for W phase. The excessive graphite plays a very important role in the formation of cubic phase, otherwise the h.c.p. phase is formed. The entropy evaluation shows that the reduction reaction is a self-propagating process. After millimg for 90 hours and excluding MgO from the product by using HCl solution, the cubic substoichiometric WC1 − z powders containing a little excessive graphite with the grain size in the range of 4 to 20 nm were obtained.
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Tan, GL., Wu, XJ., Zhao, MH. et al. Synthesis of nanocrystalline cubic substoichiometric WC1 − z powders by mechanochemical technology. Journal of Materials Science 35, 3151–3154 (2000). https://doi.org/10.1023/A:1004880221909
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DOI: https://doi.org/10.1023/A:1004880221909