Thermodynamics and fragility of glass-forming alloys

JOURNAL OF ALLOYS AND COMPOUNDS

卷:586

Article

Battezzati, L.¹ 

[1] Univ Turin, Dipartimento Chim, I-10125 Turin, Italy

关键词: Metallic glasses;    Amorphous materials;    Thermodynamic properties;    Viscosity;   

DOI  :  10.1016/j.jallcom.2012.10.027

来源: Elsevier

【 摘 要 】

The existing correlation between the extensive properties, Delta H and Delta S, the enthalpy and entropy difference between liquid and crystal phases has been checked to relate metallic glasses to other classes of amorphous materials. Expressing the specific heat difference, Delta C-p, of molten and crystalline metallic glass-formers as a function of temperature with different functional trends, parametric expressions of fragility are derived using relevant temperatures for alloys. It is shown that relationships between the Delta S-g/Delta C-p,C-g ratio and such temperatures are useful to estimate unknown quantities when the experimental determination of the specific heat is possible. Thermodynamic indicators of fragility are compared to the kinetic fragility obtained from viscosity data accounting for the estimated errors on parameters which are derived from extrapolations. The outcome of the analysis indicates that a relationship between thermodynamic and kinetic parameters exists. Moreover a systematic scatter for some alloys indicates a diverse behavior which can be ascribed to structure modification either in the liquid or in the solid reference state. (C) 2012 Elsevier B.V. All rights reserved.

【 授权许可】

Free