Abstract

LEIVA, Daniel Rodrigo et al. Magnesium-Nickel alloy for hydrogen storage produced by melt spinning followed by cold rolling. Mat. Res. [online]. 2012, vol.15, n.5, pp. 813-817.  Epub Aug 09, 2012. ISSN 1516-1439.  http://dx.doi.org/10.1590/S1516-14392012005000096.

Severe plastic deformation routes (SPD) have been shown to be attractive for short time preparation of magnesium alloys for hydrogen storage, generating refined microstructures and interesting hydrogen storage properties when compared to the same materials processed by high-energy ball milling (HEBM), but with the benefit of higher air resistance. In this study, we present results of a new processing route for Mg alloys for hydrogen storage: rapid solidification followed by cold work. A Mg₉₇Ni₃ alloy was processed by melt spinning (MS) and by extensive cold rolling (CR). Submitting Mg₉₇Ni₃ ribbons between steel plates to cold rolling has shown to be a viable procedure, producing a thin cold welded foil, with little material waste. The as-processed material presents a high level of [002] fiber texture, a sub microcrystalline grain structure with a high density of defects, and also a fine dispersion of Mg₂Ni nanoparticles. This refined microstructure allied to the developed texture resulted in enhanced activation and H-sorption kinetics properties.

Keywords : hydrogen storage materials; metal hydrides; severe plastic deformation.