|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Bulk Metallic Glasses XIX
||Chemical and Topological Frustration in Binary Metallic Glass Formation
||Yuanchao Hu, Jan Schroers, Mark D. Shattuck, Corey S. O'Hern
|On-Site Speaker (Planned)
Although many thermodynamic parameters have been correlated with glass-forming ability (GFA), a comprehensive understanding of the microscopic mechanisms for GFA is still lacking. In recent studies, we performed large-scale molecular dynamics simulations of Lennard-Jones systems to investigate the effects of several elemental features, including cohesive energy, atomic symmetry, and size ratio, on glass formation in binary alloys. We find that topological frustration, like locally favored icosahedral structures, contributes to glass formation, but these structures also promote quasi-crystal formation. More importantly, we find that the amount of chemical frustration, characterized by the degree to which local concentration of different atom types deviates from that in the liquid state, provides an accurate prediction of the GFA. In addition, we describe a new mechanism of bond shortening that can explain the GFA of many alloys. We anticipate that our findings will also be relevant for understanding the GFA in ternary and multicomponent alloys.
||Modeling and Simulation, Solidification,