STRUCTURAL CHARACTERIZATION AND REVERSIBLE HYDROGEN ABSORPTION PROPERTIES OF MG2NI RICH NANOCOMPOSITE MATERIALS SYNTHESIZED BY MECHANICAL ALLOYING

Starting from a mixture of Mg and Ni with an atomic ration of 3:1 and using a planetary ball mill, we have successfully elaborated a Mg2Ni r ich nanocomposite material formed by the Mg2Ni phase, some residual Ni and an amorphous phase. The synthesis of this composite proceeded at milling intensities 10 and 7, corresponding respectively to 10 and 3.5 W g(-1) shock power, respectively after 4 and 18 h. The best hydrogen absorption capacity reported, 3.53 wt % (3.75 H/mole), is for the com posite synthesized at 3.5 W g(-1) shock power and 24 h mechanical allo ying time. These mechanical alloying time and hydrogen absorption capa city are better than those reported up today [18,3]. (C) 1998 Elsevier Science S.A.