Evaluations of Microstructure and Hydrogenation Properties on Mg₂NiHx Hydrogen Absorbing Alloys by Hydrogen Induced Mechanical Alloying

Abstract:

In order to fabricate high efficiency, light-weight hydrogen storage materials in an economical way, we have been made to propose a new mechanical alloying process by high-pressure hydrogen induced planetary ball milling(HIMA) using Mg and Ni chips. Microstructural evaluations of the Mg-Ni-H systems synthesized were investigated by scanning electron microscopy and the transmission electron microscopy. X-ray diffraction analysis was also made to characterize the lattice constant, crystallite size and misfit strain. The hydrogenation properties of the particles synthesized were evaluated by automatic PCI (pressure-composition-isotherm). Adopting 66:1 BCR (ball to chips mass ratio) for HIMA process, fully hydrogenated alloys were obtained after 96 hrs of milling, resulting in total hydrogen content of 2.25 mass%.

• Periodical: Materials Science Forum (Volumes 544-545)
• Pages: 311-314
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.544-545.311
• Online since: May 2007
• Authors: Whan Gi Kim, Soon Chul Ur, Y.G. Lee, Young Jig Kim, Tae Whan Hong
• Keywords: HIMA, Hydrogen Absorbing Alloy, Hydrogenation Properties, Mg₂NiH_x, PCI

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