Microstructure and hydrogenation behavior of ball-milled and melt-spun Mg–10Ni–2Mm alloys

• Published in: Journal of alloys and compounds 2008-10, Vol.466 (1), p.176-181
• Main Authors: Wu, Y., Han, W., Zhou, S.X., Lototsky, M.V., Solberg, J.K., Yartys, V.A.
• Format: Article
• Language: English
• Subjects: Applied sciences; Chemical and electrochemical properties; Exact sciences and technology; Hydrogen-absorbing materials; Metal powders; Metals. Metallurgy; Microstructure; Powder metallurgy. Composite materials; Production techniques; Rapid-solidification; Transmission electron microscopy
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2007.11.128

Microstructure and hydrogen storage properties of a melt-spun Mg–10Ni–2Mm (at.%) alloy were studied in comparison with those of a conventionally prepared ball-milled one. The kinetics of H-absorption/desorption was improved through melt-spinning by obtaining nanograins in an amorphous matrix. The melt-spun ribbon alloy and the 2 h ball-milled alloy reached a maximum hydrogen storage capacity of ∼4.2 wt.% in 141 min and ∼3.2 wt.% in 210 min, respectively. Vacuum temperature desorption spectroscopy (TDS) (heating rate 5 °C/min) of the melt-spun alloy showed narrower desorption temperature range (220–330 °C), displaying a sharp joint peak at ∼286 °C than the 2 h ball-milled one (250–425 °C) with a broad peak around ∼310 °C. The species of hydrides were closely related to the microstructure. TEM micrographs and a sharp TDS peak demonstrated that the grains remained nano-sized in the melt-spun ribbons even after heating up to 350 °C during cycles.