A separation between oxygen removal and phase transition: A new path for preparing nano-scale tungsten carbide powder

Abstract In this work, adopting tungsten blue oxide (TBO, W10O29 as main phase) as precursor, nano tungsten powder and nano tungsten carbide powder were successfully prepared through two steps of hydrogen reduction and carbonization. In tungsten powder preparation, it was found that the essence of β-W transition was a separation between oxygen removal and phase transition. Based on nucleation energy control, nano tungsten powder with a BET value as high as 25.55 m2/g was prepared. On this basis, nano tungsten carbide powder with a BET value of 3.87 m2/g, which is at a leading level, was obtained by adopting a high temperature-short time process.