Relationship of structural disorder and stability of supercooled liquid state with glass-forming ability of metallic glasses

Abstract: We performed calorimetric studies of 26 metallic glasses and calculated the excess entropy and excess enthalpy with respect to their counterpart crystals. On this basis, we introduced a dimensionless entropy-based parameter {\sigma}scl, which characterizes structural disordering and stability of the supercooled liquid state upon heating. A very good correlation of {\sigma}scl with literature data on the critical cooling rate Rc and critical diameter Dmax of metallic glasses is shown. We also introduced another dimensionless parameter {\eta}scl based on the excess enthalpy of glass and showed that {\eta}scl provides equally good correlation with Rc and Dmax. Possible relationship of structural disordering and glass-forming ability in the supercooled liquid range with the defect structure of glass is discussed. The obtained results provide a new window for the understandingof the glass-forming ability of metallic glasses.