Mechanochemical synthesis of tungsten carbide nano particles by using WO3/Zn/C powder mixture

In this research we introduce a new, facile, and economical system for fabrication of tungsten carbide (WC) nano particle powder. In this system WO3, Zn, and C have been ball-milled for several hours, which led to the synthesis of tungsten carbide nano particles. The synthesized WC can successfully be separated from the ball-milled product by subjecting the product powder to diluted HCl for removing ZnO and obtaining WC. X-ray diffraction (XRD) analysis indicates that the reduction of WO3 will be completed gradually by increasing milling time up to 36 h. Scanning electron microscope (SEM), and transmission electron microscope (TEM) images show that after 36 h of milling the particle size of the fabricated powder is nano metric (about 20 nm). Results have shown that this system can surmount some main problems occurred in previous similar WC synthesizing systems. For example carbothermic reduction reactions, which lead to the synthesis of W2C instead of WC, would not be activated because in this system reactions take place gradually.