Synthesis of vanadium carbide by mechanical alloying

Vanadium carbide was synthesized by ball milling V2O5, Mg and graphite powders at room temperature using a planetary ball mill. Characterization of the structural evolution during milling was carried out using X-ray diffractometry (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Experimental results indicate that the formation of vanadium carbide is a self-sustained reaction. The as-produced VCx (x < 1) has the same structure as VC. When VCx was annealed at a temperature higher than about 750 °C, it transforms into V8C7. The formation mechanism of vanadium carbide is discussed.