Hydriding characteristics of Mg-Ti alloys prepared by reactive mechanical grinding and hydrogen pulverization

Nanocrystalline Mg and Mg-10Ti hydrogen-storage alloys were prepared by reactive mechanical grinding combining with hydrogen pulverization. The synthesis was done at room temperature under 3 atm of hydrogen using a planetary ball milling device for 6 h. The surface area of the Mg-10Ti alloy was further increased from 0.61 to 6.16 m2/g when the milled alloy was pulverized by hydrogenation at 350 ̊C. The morphological and microstructural characteristics were investigated by scanning electron microscopy, X-ray diffraction, and transmission electron microscopy. After the reactive mechanical grinding and hydrogen pulverization, the particle size of the powder was reduced and magnesium hydride was formed. The addition of titanium efficiently inhibited the oxidation of magnesium during alloying process. Furthermore, the hydrogen storage characterization revealed that the addition of titanium improved the hydrogen absorption capacity of 3.63 wt% as compared with that of Mg (3.36 wt%). Mg-10Ti alloy has an improved absorption capacity and decreased hysteresis.