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

In the present work, we report on hydride formation in an Mg-ZrFe1.4Cr 0.6 composite. The thermodynamic properties, the hydrogen absorption a nd desorption kinetics at different temperatures, the cycling properti es, and the resistance to oxidation were examined. The two phases of t he composite, i.e. Mg and the alloy, retained their original thermodyn amic properties upon repeated cycling. The hydrogen absorption and des orption in the composite were rapid, even at moderate temperatures (15 0-degrees-C). The Mg particles were found to be partially covered by t he 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 determine d by standard volumetric methods. Structural and chemical analyses wer e performed by X-ray diffraction, scanning electron microscopy, energy -dispersive X-ray spectroscopy, transmission electron microscopy and s elected-area diffraction.