Microstructural evolution of shear bands formation of metallic glasses under different loading conditions and strain rates

The shear bands (SBs) evolution of Cu50Zr50 metallic glasses (MGs) by the uniaxial loading under different strain rates are investigated on the temporal and spatial scales using the molecular dynamics (MD) simulation. The stress-strain curve shows a corresponding relation to the microstructure parameter curve in the form of four-stage, together with a synchronized evolution of multiple shear bands. During the propagation of the dominate shear band (DSB), the rearrangement of global microstructure is induced by the different transformation of three categories of clusters located in different zones. The synchronized evolutions of the microstructure, the deformation and the mechanical property are found to be less affected by loading condition or strain rate. However, with the increase of strain rate, the initiation and propagation of the DSB are observably retarded. As a consequence, the fracture mode of the MGs presents a change from a sliding along the DSB to a uniform deformation.

Automated summary

In this study, the evolution of shear bands in Cu50Zr50 metallic glasses under different strain rates was investigated using molecular dynamics simulation. The results showed that the synchronized evolutions of microstructure, deformation, and mechanical properties were less affected by loading conditions or strain rates. However, an increase in strain rate resulted in a noticeable retardation of the initiation and propagation of the dominate shear band, leading to a change in the fracture mode of the metallic glasses.