Local atomic structures of amorphous Pd80Si20 alloys and their configuration heredity in the rapid solidification

The local atomic structures of amorphous Pd80Si20 alloys and their configuration heredity in the rapid solidification are investigated by a molecular dynamics simulation with the help of cluster-type index method based on Honeycutt-Anderson bond-type index and an inversely tracking technique of atomic trajectories. Their short-range orders are found to be various Kasper clusters as well as their distorted configurations, and among which (10 2/1441 8/1551) bi-capped square Archimedean anti-prism (BSAP) clusters are dominated, e.g. Si-centred Pd10Si1 clusters. These Kasper clusters mainly exist in the form of isolated basic clusters. Few medium-range orders can be detected, especially for Si-centred Kasper clusters. Similarly to icosahedrons of Cu-Zr amorphous alloys, their sustainable configuration heredity also occurs firstly in the super-cooled liquid region, and BSAP clusters have higher onset temperature T-onset and bigger descendible fraction F than other Kasper clusters in the rapid solidification of Pd80Si20 alloys.