Thermodynamic Properties of Pt-Cu-P Bulk Metallic Glasses

Ultra-fragile Pt-Cu-P metallic glasses and their thermodynamic properties have been systematically investigated using differential scanning calorimetry. The thermodynamic functions of excess enthalpy, entropy, and Gibbs free energy between the liquid and crystal phases were calculated as a function of Cu content from the isobaric specific heat capacity measurements of the glass, crystal and liquid phase. The glass transition, crystallization, and liquidus temperatures, and the enthalpies of crystallization and melting were also assessed. New calorimetry results, coupled with statistical analysis, suggest a high likelihood of insufficiency of the Kubaschewski equation in accommodating heat capacity in the supercooled liquid phase for some metallic glasses. These results will be discussed in the context of previous work on these glasses which introduced a more general empirical form for the liquid configurational enthalpy [1].<br/><br/>1. Na, J.H., et al., P.N.A.S. 117, 2779 (2020).