Manifestation of Dynamic Anomaly in Metallic Glass-Forming Liquids by Their Crystallization Processes

More and more evidence has indicated the general existence of fragile-to-strong transition (FST) in metallic glass-forming liquids (MGFLs), but the thermodynamic properties corresponding to this dynamic anomaly remain unclear. For rare earth-based metallic glasses, the crystallization process is of importance to understand the dynamic anomaly of their supercooled liquids. In the present work, we studied the effects of thermal history (including cooling rate of fabrication, aging temperature and DSC scanning rate) on the crystallization behaviors of Ce-based, Pr-based and La-based hyperquenched glasses. Abnormal changes of crystallization processes were found in all these three rare-earth-based metallic glass ribbons, despite the distinct difference in their respective specific behaviors. The general non-monotonic change of crystallization characteristics corresponds to the non-monotonic structural evolution of supercooled liquid at a certain fictive temperature, which just falls in the temperature range where the fragile-to-strong transition occurs. Based on the observed abnormal crystallization behavior and its relation to the dynamic anomaly in supercooled liquids, as well as the convenience and reliability of measuring thermodynamic properties, we expect to provide a deep insight into the evolution of the supercooled metallic liquids.