The deformation and transformation of icosahedron in Mg70Zn30 metallic glasses

Highlights: • Two kinds of deformed icosahedrons are identified based on slight change of one pair. • The transforming pathways between icosahedron and the two deformed icosahedrons are discussed. • The structure of icosahedron is the most stable by measuring the relative rate M. A molecular dynamics simulation is performed to investigate the icosahedron in Mg₇₀Zn₃₀ metallic glass during solidification at the cooling rate of 1 × 10¹³ K/s. It is found that the 1551, 1541 and 1431 bond-types are closely related to 13-atom icosahedron-like clusters. Two kinds of clusters are very similar to full icosahedron in geometry. The three clusters can transform into each other by changing one bond between a pair of outer atoms. One distorted icosahedron act as the intermediate between the two others. This work provides an insight into the glass formation in alloy from the cluster-level structural viewpoint and will shed light on developing more metallic glasses.