Changes in intermittent serrated flow behavior during plastic deformation of Zr 64.13 Cu 15.75 Ni 10.12 Al 10 , a representative glassy metal with characteristic ductility, in response to variant strain rates and temperatures were examined. The influence of strain rates and environmental temperatures on the stress-time sequence of the plastic strain regime was investigated using comprehensive dynamical, statistical, and multifractal analyses. Three distinct spatiotemporal dynamical regimes were explored. Under small strain rates or high temperatures, the time-stress sequence exhibited a chaotic behavior. Conversely, under large strain rates or low temperatures, a transition to the self-organized critical (SOC) state was observed. In addition to chaotic time series and statistical analysis, multifractal analysis was also applied to study the crossover between these two unique plastic dynamic transitions. This plastic dynamical behavior was elucidated based on the interactions between shear avalanches in the glassy metal.

A model Zr41.25Ti13.75Ni10Cu12.5Be22.5 (at.%) bulk metallic glass (BMG) is selected to explore the structural evolution on the atomic scale with decreasing temperature down to cryogenic level using high energy X-ray synchrotron radiation. We discover a close correlation between the atomic structure evolution and the strength of the BMG and find out that the activation energy increment of the concordantly atomic shifting at lower temperature is the main factor influencing the strength. Our results might provide a fundamental understanding of the atomic-scale structure evolution and may bridge the gap between the atomic-scale physics and the macro-scale fracture strength for BMGs.

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