Processing by controlled mechanical milling of nanocomposite powders Mg+X (X = Co, Cr, Mo, V, Y, Zr) and their hydrogenation properties

Controlled mechanical milling under high-energy impact (impact 2) mode in the magneto-mill Uni-Ball-Mill 5 was applied for processing of nanocomposite powders Mg + X (X = Co, Cr, Mo, V, Y, Zr) in order to develop novel nanoscale Mg-based materials with improved hydrogen storage properties through nanostructurization and possible catalytic effect of additive metal. No mechanical alloying has occurred between Mg and the catalytic metals after milling for 20 h. Catalytic metals such as Co, Cr, V, Y and Zr improve the absorption kinetics very substantially. Only the nanocomposite Mg/Mo has the hydrogenation kinetics much worse than that of a single-phase Mg. No correlation between the crystallite (nanograin) size of catalytic metals and the hydrogen absorption kinetics is observed. (c) 2005 Elsevier B.V. All rights reserved.