  New ternary Mg-Ni-Mn intermetallics have been successfully synthesized by
High Energy Ball Milling (HEBM) and have been studied as possible materials for
efficient hydrogen storage applications. The microstructures of the as-cast and
milled alloys were characterized by means of X-ray Powder Diffraction (XRD) and
Scanning Electron Microscopy (SEM) both prior and after the hydrogenation
process, while the hydrogen storage characteristics (P-c-T) and the kinetics
were measured by using a commercial and automatically controlled Sievert-type
apparatus. The hydrogenation and dehydrogenation measurements were performed at
four different temperatures 150-200-250-300oC and the results showed that the
kinetics for both the hydrogenation and dehydrogenation process are very fast
for operation temperatures 250 and 300oC, but for temperatures below 200oC the
hydrogenation process becomes very slow and the dehydrogenation process cannot
be achieved.
