Tungsten Carbide - Synthesis

Synthesis

WC can be prepared by reaction of tungsten metal and carbon at 1400–2000 °C. Other methods include a patented fluid bed process that reacts either tungsten metal or blue WO3 with CO/CO2 mixture and H2 between 900 and 1200 °C. WC can also be produced by heating WO3 with graphite in hydrogen at 670 °C following by carburization in Ar at 1000 °C or directly heating WO3 with graphite at 900 °C. Chemical vapor deposition methods that have been investigated include:

  • reacting tungsten hexachloride with hydrogen, as a reducing agent, and methane, as the source of carbon at 670 °C (1,238 °F)
WCl6 + H2 + CH4 → WC + 6 HCl
  • reacting tungsten hexafluoride with hydrogen, as reducing agent, and methanol, as source of carbon at 350 °C (662 °F)
WF6 + 2 H2 + CH3OH → WC + 6 HF + H2O

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