Paper Title:

Gibbs Free Energy Difference in Bulk Metallic Glass Forming Alloys

Periodical Defect and Diffusion Forum (Volume 279)
Main Theme Phase Transformation and Diffusion
Edited by G. B. Kale, M. Sundararaman, G. K. Dey and G. P. Tiwari
Pages 91-96
DOI 10.4028/www.scientific.net/DDF.279.91
Citation Heena Dhurandhar et al., 2008, Defect and Diffusion Forum, 279, 91
Online since August, 2008
Authors Heena Dhurandhar, Kirit N. Lad, Arun Pratap, G.K. Dey
Keywords Bulk Metallic Glass (BMG), Gibbs Free Energy, Specific Heat Difference, Under Cooled Region
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Abstract

The Gibbs Free Energy Difference between the solid and liquid phases (DG) is related to nucleation frequency and has played an important role in predicting the glass forming ability (GFA) of multicomponent metallic alloys. This is due to the fact that the maximum energy for nucleus formation i.e. the activation barrier for nucleation has an inverse square relation with DG. The Gibbs Free Energy Difference of three multi-component bulk metallic glasses namely Mg65Cu25Y10, Zr57Cu15.4Ni12.6Al10Nb5 and Zr52.5Cu17.9Ni14.6Al10Ti5 have been evaluated using two new expressions. The results show that the DG values calculated assuming DCp to be constant lie closer to the experimental values for the Mg based system while in the case of two Zr based systems, DG computed using the hyperbolic variation of DCp show improved agreement with the experimental data.