Thermodynamic and mechanical properties of Zr-based bulk metallic glasses

Abstract

Glasses are generally produced from the highly undercooled liquid state by rapid quenching methods or quasistatically at slow cooling by the effective control of potent heterogeneous nucleation sites. For metallic systems the latter method recently has led to the development of bulk metallic glasses, so-called supermetals, with a complex multicomponent chemistry and advanced engineering properties. As long as crystallization can be prevented, the relevant thermodynamic properties of the metastable glassy and undercooled liquid phases can be measured below and above the glass transition temperature respectively. The data suggest that the glass transition corresponds to kinetic freezing triggered by an underlying entropic instability. Further measurements of the mechanical and wear properties of these new metastable materials point to unique engineering properties for technological applications.