Hydrogen sorption behavior of mechanically synthesized Mg–Ag alloys

Hydrogen Sorption Behavior of Cast Ag-Mg Alloys

“…Therefore, these results are not shown. Furthermore, the results (two-step plateau) confirm that hydrogen sorption proceeds in several steps, in which it is very likely that magnesium reacts with hydrogen to form magnesium hydride, and the ε or AgMg 4 phases react with hydrogen to form stable AgMg and MgH 2 phases, as mentioned previously [ 15 , 16 ]. As a result of these reactions, the AgMg phase formed in the system does not react with hydrogen and blocks the absorption and desorption processes.…”

“…The obtained results (temperatures) are in very good correlation with the data obtained by mechanical alloying followed by annealing [ 16 ] however, split peaks for AgMg were not observed for the case of mechanically alloyed samples, so it is probable that this specific behavior is specific only for cast material, perhaps due to the relatively large size of the filings and slow hydrogen diffusion in the material.…”

“…This phase has been found previously in cast alloys, as described by Arakcheeva et al [ 17 ]. Later, Pęska et al [ 16 ] observed mechanically alloyed and annealed samples and found that they readily react with hydrogen at elevated temperatures.…”

“… Representation of the chemical composition of the fabricated Mg-Ag samples on the Ag-Mg phase diagram. Diagram based on [ 16 ]. …”

“…They observed that the addition of silver to Mg slightly improves the hydrogen absorption and desorption kinetics, while further destabilization reactions were observed. Most recently, Pęska et al [ 16 ] showed the relationships for mechanically synthesized magnesium-silver alloys after both milling and annealing. It was shown that all compositions with silver concentrations lower than that for AgMg readily react with hydrogen, although the mechanism is different for different compositions and in agreement with that reported previously by Si et al and Urretavizcaya et al [ 14 , 15 ].…”