Characterizing thermodynamic properties of Ti-Cu-Ni-Zr bulk metallic glasses by hyperbolic expression

The hyperbolic expression of specific heat difference, Delta C-p, in the supercooled liquid and corresponding crystalline phase of bulk metallic glasses can be deduced based on the expression of Delta C-p in the hole theory of the liquid state. According to the hyperbolic expression of Delta C-p, novel expressions of the Gibbs free energy difference, Delta G, enthalpy difference, Delta H, and entropy difference, Delta S, between the supercooled liquid and corresponding crystalline phase may be estimated. The experimentally measured thermodynamic parameters of Ti35.37Cu45.11Ni8.88Zr10.64 and Ti37.65Cu43.25Ni9.6Zr9.5 bulk metallic glasses exhibit a perfect fit with these novel expressions for Delta G, Delta H and Delta S. This finding clearly suggests that the hyperbolic expression of Delta C-p provides an optimum mathematical model for the elucidation of glass forming ability, with increased accuracy and ease of modeling compared to previously reported expressions. (C) 2012 Elsevier B.V. All rights reserved.