Formation of magnesium nanocomposite via mechanical milling

Nanocomposite Mg5wt%Al has been synthesized via mechanochemical milling of elemental Mg, Al and Ti powders with polyethylene-glycol. TiH2 phase was formed through the reaction between Ti and polyethylene-glycol during the milling as well as the sintering processes. Formation of ultra-fine particles of a few nanometer in size was observed within the matrix grains. The formation of TiH2 particles is hypothesized to occur through two stages. In the first stage, Ti is supersaturated in the Mg matrix during high energy milling while polyethylene-glycol decomposes to react with Mg as well as Ti which is not solid solute in the Mg matrix. In the second stage during sintering, the hydrogen and Ti released from the Mg react with each other, thus forming nanoparticles. As a result of the nanoparticles, the nanocomposite manifests improved yield strength and ductility in comparison to it counterpart. (C) 2004 Elsevier Ltd. All rights reserved.