Concentration-dependent Cluster Heredity and Evolution Mechanism of Glass Forming Ability in Pd–Si Amorphous Alloys

The molecular dynamics method has been employed to simulate the rapid solidification process of Pd_100–xSi_x (x=10, 20, 30, 40, 50) alloys. An analysis is conducted on the concentration-dependent mechanism of cluster inheritance and evolution and its impact on the glass forming ability (GFA). The GFA of Pd–Si amorphous alloys exhibits a non-monotonic relationship with Si concentration. Optimal Si concentration can enhance GFA significantly, while a minimal amount of Si can lead to system over-ordering, thereby weakening its GFA. The analysis of cluster inheritance and evolution indicated that low-coordination clusters demonstrated higher heritability during rapid solidification compared to high-coordination and icosahedral clusters, thus effectively improving the GFA of Pd–Si systems. Specifically, (10 2/1441 8/1551) clusters exhibited the highest evolution fraction and heritability among all components, underscoring their pivotal role in enhancing the GFA of Pd–Si amorphous alloys.