The reduction of V2O5 using Mg, Al, and Ti as reductants during mechanical milling in a ball mill has been studied. With all three reductants, a combustion reaction was observed after milling for a critical ignition time. Using Mg as the reductant, the ignition time was found to increase with decreasing collision energy. However, the combustion event could not be associated with a critical degree of microstructural refinement or a reduction of the ignition temperature. With both Mg and Al reductants TEM examination of the as-combusted powders showed the presence of nanoscale single crystal smoke particles, similar to those formed by gas evaporation techniques. (C) 1994 Academic Press, Inc.