HYDRIDE FORMATION IN MG-ZRFE1.4CR0.6 COMPOSITE-MATERIAL

In the present work, we report on hydride formation in an Mg-ZrFe1.4Cr0.6 composite. The thermodynamic properties, the hydrogen absorption and desorption kinetics at different temperatures, the cycling properties, and the resistance to oxidation were examined. The two phases of the composite, i.e. Mg and the alloy, retained their original thermodynamic properties upon repeated cycling. The hydrogen absorption and desorption in the composite were rapid, even at moderate temperatures (150-degrees-C). The Mg particles were found to be partially covered by the alloy. The alloy islands acted as a catalyser for the dissociation and recombination of hydrogen atoms. Furthermore, the alloy overlayer protected the Mg from oxidation during sorption cycles and exposure to the atmosphere. The hydrogen absorption and desorption were determined by standard volumetric methods. Structural and chemical analyses were performed by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy and selected-area diffraction.