Process and Mechanism of WC Nano-powders Prepared by Carbon-Hydrogen Coreduction-Carbonization Method

作者：Ye Nan; Tang Jiancheng^*; Wu Aihua; Wei Xiaoxiao

来源：Rare Metal Materials and Engineering, 2017, 46(1): 143-149.

• carbon-hydrogen coreduction
• tungsten carbide nano-powders
• volatilization-deposition
• reaction temperature

Due to the growth of WC particles in the traditional reduction and carbonization process, the method of carbon-hydrogen coreduction-carbonization was adopted to prepare WC nano-powders and the effects of the n(C)/n(W) of precursors and reaction temperature on the properties of WC were studied. The results show that the carbon content of WC is related to the n(C)/n(W) of precursors, and the optimum molar ratio is 3.6. The average particle size of WC is closely related to reduction temperature and carbonization temperature because the transformation of W to WC has structural heredity. With the reduction temperature increasing from 680 degrees C to 800 degrees C, the pressure of water vapor in the system decreases due to the reaction of H2O and C, which inhibits the volatilization-deposition growth of W particles in the hydrogen reduction process. Therefore, the average particle size of WC decreases with the increasing of reduction temperature. The high temperature can promote the grain boundary migration of WC particles and the combination growth of W nano-particles, and the average particle size of WC increases with the increasing of carbonization temperature.

• 出版日期2017-1
• 单位南昌大学