Notable hydriding properties of a nanostructured composite material of the Mg{sub 2}Ni-H system synthesized by reactive mechanical grinding

Journal Article · Wed Jan 01 04:00:00 EST 1997 · Acta Materialia

DOI:https://doi.org/10.1016/S1359-6454(96)00158-9· OSTI ID:445346

Orimo, S; Fujii, H; Ikeda, K ^[1]

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1. Hiroshima Univ., Higashi-Hiroshima (Japan). Faculty of Integrated Arts and Sciences

The intermetallic compound Mg{sub 2}Ni was mechanically ground under a hydrogen atmosphere to synthesize a nanostructured composite material that is composed of nanocrystalline intra-grain and disordered inter-grain regions. Both the thermal and magnetic analyses confirmed that a volume fraction of the latter region increases twenty times as much as that in the initial compound, nearly 30%, by grinding for only 60 min. As a result of this structural modification, notable hydriding properties emerged; the dissolved hydrogen content reaches up to 1.6 wt% (Mg{sub 2}NiH{sub 1.8}) without changing the crystal structure (Mg{sub 2}Ni type) of the nanocrystalline intragrain region, and the cooperative dehydriding reaction between both the regions occurs even at 413 K. The hydriding properties are most likely reversible in the temperature ranges below 473 K, above which the disordered inter-grain region transforms into a crystalline phase.

• OSTI ID: 445346
• Journal Information: Acta Materialia, Journal Name: Acta Materialia Journal Issue: 1 Vol. 45; ISSN 1359-6454; ISSN ACMAFD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPOSITE MATERIALS
EXPERIMENTAL DATA
INTERMETALLIC COMPOUNDS
MAGNESIUM ALLOYS
MAGNESIUM HYDRIDES
MAGNETIC PROPERTIES
MICROSTRUCTURE
MILLING
NICKEL
NICKEL HYDRIDES
SYNTHESIS
TEMPERATURE DEPENDENCE
THERMAL ANALYSIS