Study on glass-forming ability and hydrogen storage properties of amorphous Mg60Ni30La10 - xCox (x=0, 4) alloys

Mg60Ni30La10 - Co-x(x) (X = 0, 4) amorphous alloys were prepared by rapid solidification, using a melt-spinning technique. X-ray diffraction and differential scanning calorimetry analysis were employed to measure their microstructure, thermal stability and glass-forming ability, and hydrogen storage properties were studied by means of PCTPro2000. Based on differential scanning calorimetry results, their glass-forming ability and thermal stability were investigated by Kissinger method, Lasocka curves and atomic cluster model, respectively. The results indicate that glass-forming ability, thermal properties and hydrogen storage properties in the Mg-rich corner of Mg-Ni-La-Co system alloys were enhanced by Co substitution for La. It can be found that the smaller activation energy (AE) and frequency factor (nu(0)), the bigger value of B (glass transition point in Lasocka curves), and higher glass-forming ability of Mg-Ni-La-Co alloys would be followed. In addition, atomic structure parameter (X), deduced from atomic cluster model is valuable in the design of Mg-Ni-La-Co system alloys with good glass-forming ability. With an increase of Co content from 0 to 4, the hydrogen desorption capacity within 4000 s rises from 225 to 2.85 wt.% at 573 K. (C) 2013 Elsevier Inc. All rights reserved.