Synergism of mechanical milling and dielectric barrier discharge plasma on the fabrication of nano-powders of pure metals and tungsten carbide

In the present work, a new mechanical alloying method, which combines ball milling and dielectric barrier discharge plasma (DBDP) together, has been reported. By treating pure metals, such as Al, Fe and W and synthesis WC with this method, an obvious synergism of ball milling and DBDP has been revealed, which is characterized by concurrent action of high temperature and stress on the powder in a very short time. Owing to the synergism of ball milling and DBDP, the fabricated metal powder has unique features, such as lump-like morphology with very fine primitive particles and high specific surface area. The chemical activity of the powders is very high, which makes possible the formation of nanostructured tungsten carbides at a temperature much lower than that in conventional carburizing of W. This provides a potential method for fabricating ultra fine powders and synthesizing metal ceramics. (C) 2008 Elsevier B.V. All rights reserved.