Synthesis of titanium carbonitride nano-powder by carbothermal reduction of TiO2

The effects of oxide addition on the carbothermal reduction of fine TiO2 were studied for obtaining nano-powders. MoO3, WO3, ZrO2, Nb2O5 and Ta2O5 were used as additives. Each additive was mixed with TiO2 and C powder. The mixed powder was heat treated in flowing Ar up to 1500 °C. It was confirmed that MoO3 and WO3 were effective in yielding fine particles with size of about 0.1-0.2 μm. The addition of MoO3 resulted in the restriction of grain growth of the TinO2n − 1 phase. The calculation of vapor pressure of the added oxides indicated that the vapor pressure of MoO3 was highest among the oxides explored under an inert atmosphere. This suggested that Mo compounds were easily spread through the gas phase and were homogeneously distributed in the powder.