Direct synthesis of tungsten carbide nanoparticles by mechanically assisted carbothermic reduction of natural wolframite

Carbothermic reduction of natural wolframite (FeWO4) to nanosized tungsten carbide (WC) particles was achieved by calcining mechanically activated mixtures of FeWO4 and active carbon at 1100 degrees C under flowing Ar gas. The average particle size ranged between 20 and 25 nm. Intermediates, Fe6W6C and Fe3W3C, were observed between 900 degrees and 1100 degrees C, which decomposed to give the final product, WC. Homogeneity increase and associated decrease in the diffusion path by milling are mainly responsible for the successful production of WC. The process paves the way to rational utilization of natural FeWO4 directly to fine advanced materials.