Synthesis of TiC Whiskers through Carbothermal Reduction of TiO2

Journal of Materials Synthesis and Processing - Tập 9 - Trang 1-10 - 2001
R. V. Krishnarao1, J. Subrahmanyam2, V. Ramakrishna2
1Defence Metallurgical Research Laboratory, Kanchanbagh, Hyderabad-, India
2Defence Metallurgical Research Laboratory, Kanchanbagh, Hyderabad, India

Tóm tắt

TiC whiskers were produced through carbothermal reduction of TiO2 in the presence of potassium (K2CO3) and nickel (NiCl2). The effect of potassium, nickel, and heating rate on the formation of whiskers was studied. Potassium was found to be an essential constituent for whisker formation. Nickel acts as a catalyst for TiC whisker formation only in the presence of potassium. The yield of whiskers was maximum at 1000–1200°C. At higher temperatures, formation of particulates of TiC was the dominant process. An increase in K2CO3 concentration during fast heating and decrease in K2CO3 concentration during slow heating was found to be beneficial in increasing the formation of TiC whiskers. A vapor–liquid–solid growth mechanism of whisker formation was explained.

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