Excess Entropy of Metallic Glasses and Its Relation to the Glass-Forming Ability of Maternal Melts

The excess entropy ΔS with respect to the maternal crystal state has been determined from calorimetric data for 30 metallic glasses. It has been shown that the excess entropy in the supercooled liquid state ΔS_sql is a universal characteristic of a glass independent of its thermal treatment. Six parameters often used to estimate the glass-forming ability of supercooled melts have been calculated for the same metallic glasses. It has been shown that all six parameters increase with ΔS_sql and the glass-forming ability of supercooled melts increases with their structural disorder. A possible mechanism to implement this relation has been discussed.