Effect of Particle Size on the Oxidation of WC Powders during Heating

摘要

The oxidation of tungsten carbide powders ranging in average particle size D from 20 to 6000 nm has been studied by thermal analysis. Independent of particle size, the WC powders oxidize to the higher oxide WO_3. With decreasing particle size, the oxidation rate increases, and the exothermic peak temperature decreases. Empirical relations are presented for the peak temperature and activation energy of oxidation as functions of the particle size of the powders.