Berlouis, L.E.A. and Aguado, R.P. and Hall, P.J. and Morris, S. and Chandrasekaran, L. and Dodd, S.B. (2003) Dehydriding kinetics of a mg-9.5 wt% v sample by high pressure differential scanning calorimetry. Journal of Alloys and Compounds, 356-357. pp. 584-587. ISSN 0925-8388Full text not available in this repository. (Request a copy from the Strathclyde author)
The effect of the additive V on the rate of hydrogen desorption from MgH2 is investigated using high-pressure differential scanning calorimetry (HP-DSC). The HP-DSC data obtained at different temperatures were analysed in terms of the nucleation and growth of the Mg phase within the hydride matrix and the subsequent movement of the phase boundary. Activation energies (EA) obtained for the different steps show that the rate determining step is very much dependent on the conditions of dehydriding. The high value of EA found (600 kJ mol−1 H) for the nucleation step suggests that the V inhibits nucleation of the α-Mg from the hydrided Mg-9.5 wt% V composite sample. This has been attributed to the precipitation of vanadium in the MgH2 matrix creating accommodation strains, leading to dislocations around the vanadium particles. These can then act as sinks for the hydrogen thereby increasing the activation energy for nucleation of hydrogen.
|Keywords:||MgH2, vapour deposition, thermal analysis, kinetics, Chemistry, Materials Chemistry, Mechanics of Materials, Metals and Alloys, Mechanical Engineering|
|Subjects:||Science > Chemistry|
|Department:||Faculty of Science > Pure and Applied Chemistry|
|Depositing user:||Strathprints Administrator|
|Date Deposited:||01 Apr 2010 10:35|
|Last modified:||27 Apr 2016 14:28|