A new method for measuring the thermodynamic properties of undercooled liquid and amorphous Cu-Zr alloys

A new method for the experimental determination of the temperature-dependent heat capacity is presented here. The value of this new method lies principally in its applicability to unstable systems, where time-dependent relaxation processes limit the utility of conventional stepwise methods that employ a series of isothermal holding periods. The method is demonstrated for two glass-forming alloys (Cu50Zr50 and Cu64.5Zr35.5), using differential scanning calorimetry (DSC) measurements over a (low) temperature regime including stable, metastable and unstable states (crystalline, glass and undercooled liquid). For this specific analysis, the glassy material is heated using several different rates, each resulting in a different transformation temperature. After characterization of the final states, analysis of the DSC traces yields the requisite transition enthalpies, enabling determination of the heat capacities, based on common reference states. (C) 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.