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Page 6 of 12 Liu et al. J Mater Inf 2022;2:20 https://dx.doi.org/10.20517/jmi.2022.29

Figure 2. Simulation results of tensile test and creep. (A): Stress-strain curve of tensile test. The inset illustrates the deformation of the
HEMG model; (B): creep strain evolution; (C): probability density distributions of T . ML: machine learning; HEMG: high-entropy metallic
ML
glasse.

100 K because of the systematic overestimation as shown in Figure 1. This peak denotes that the majority of
atoms still behave like inactive “cold” atoms and they are not fully activated by stress. Their atomic motion
is still dominated by temperature, namely thermal stimulus. However, it is worth noting that there is a fat
tail on the high T side. Such a pronounced deviation from the Gaussian distribution demonstrates the
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[34]
stress-induced heterogeneity in atomic dynamics . A small number of atoms actively respond to the
mechanical stimulus and behave like active “hot” atoms, even with T > T . With the increase of applied
ML g
creep stress, the area of the Gauss peak falls from 82% to 67%, which means that 15% net of atoms change
their motion behavior from temperature-control to stress-control. The growth of the fat tail signifies an
increasing number of active atoms. We can introduce a mechanical model [34,39] , which comprises a parallel
arrangement of a Maxwell model and a dashpot, to understand the mechanisms of the viscoelastic and
viscoplastic deformation in HEMGs. Before the active atoms coalesce, the deformation of the HEMG
behaves in a viscoelastic regime. Once the active atoms outnumber the percolation threshold, overall
[40]
viscoplastic flows will consequently take place , and the model will degenerate into a Maxwell model,
[41]
which is commonly accepted for supercooled liquids . Compared with Cu Zr [34] , the less fraction of
50 50
high-T active atoms implies the sluggish dynamics of HEMGs during the stress-induced flow.
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As displayed on a 3.8-Å-thick slice in Figure 3A, the “cold” atoms form the inactive matrix and the active
“hot” atoms lie in several isolated spots. Such an inhomogeneous map of T presents the noticeable spatial
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