Papers by Keyword: Magnesium-Nickel Alloys

Abstract: The relation of the microstructure and hydrogenation property of a hypoeutectic Mg-6.7 mol%Ni alloy consisted of primary Mg crystal and Mg2Ni phase has been investigated. In the case that the specimen has a very fine structure, hydrogen is hardly absorbed into the specimen. The growth of both the primary Mg crystal and Mg2Ni phase allow easy hydrogen penetration, but the growth of the primary Mg crystal is more effective. The highest hydrogenation rate and absorption amount of 5 mass% are obtained when the Mg2Ni phase has a rounded shape.

Abstract: We have applied hybridization method to the surface modification by Ni coating on powder specimens of pure Mg and Mg-Mg2Ni eutectic alloy, and investigated the effect of the Ni coating on the hydrogenation kinetics in them. The hydrogenation kinetics at 350 degree C is greatly increased by the Ni coating for both the pure Mg and Mg-Mg2Ni eutectic alloy specimens. Thus, it is confirmed that the surface modification by the hybridization method is considerably effective to improve the hydrogenation kinetics in them. This improvement is thought to be a catalytic effect of the coated Ni. The hydrogenation kinetics of the Mg-Mg2Ni alloy specimen heat-treated at 470 degree C has increased compared with that of the as-cast alloy specimen. It is also confirmed that hydrogenation kinetics improves by the heat treatment to grow the eutectic structure consisted of Mg2Ni phase and Mg phase.