Synthesis of a nanostructured MgH2-5 wt% Ti-Mn-V-Fe composite for hydrogen storage via combined VAR and mechanical alloying

In this study, the composite material with composition of MgH2-5wt%Ti-Mn-V-Fe has been prepared by co-milling of MgH2 powder with TiMn1.4V0.46Fe0.16 alloy powder. To prepare the alloy, vacuum arc remelting (VAR) method was applied and then the bulk was milled to reach mesh-325 alloy powders. The effect of milling time and additive on the hydrogen desorption properties of obtained composite was evaluated by thermal analysis method. The phase constituents of powder particles were characterized by X-ray diffraction method. It has been shown that addition of 5 wt% TiMn1.4V0.46Fe0.16 to MgH2 and mechanical alloying (MA) up to 30 h formed a nanocrystalline composite with the average crystallite size of MgH2 of 3 nm and lattice strain of 0.8 %, using Williamson–Hall method. As a consequence, the desorption temperature of composite material milled for 30 h has decreased to 363 °C from 421 °C.

Keywords:

Hydrogen Storage , Magnesium hydride , Mechanical alloying , Hydrogen desorption temperature