biostudies-literatureYu JMOST | National Natural Science Foundation of China (NSFC)MOST | National Natural Science Foundation of Chinae2427082122https://www.ebi.ac.uk/biostudies/studies/S-EPMC12260437biostudies-literatureUnknown122(27)Shear bands (SBs) play a critical role in determining the mechanical behavior of metallic glasses (MGs). However, the rapid dynamics and highly localized nature of SB propagation present significant challenges for direct observation of their atomistic mechanisms using experimental techniques. In this study, we employ hybrid molecular dynamics/Monte Carlo simulations to investigate the atomic-scale mechanisms of SB propagation in Mg₆₅Cu₂₅Y₁₀ MGs, prepared using cooling rates as slow as 10⁴ K s^-1-comparable to experimental casting conditions and significantly slower than the 10¹⁰ K s^-1 rates previously employed in atomistic simulations. Our results reveal a qualitative shift in SB propagation mechanisms as the strucProceedings of the National Academy of Sciences of the United States of AmericaStructural state governs the mechanism of shear-band propagation in metallic glasses.PMC1226043712004294Greer ALSha ZZhang ZYu JDing JMa EfalseStructural state governs the mechanism of shear-band propagation in metallic glasses.Shear bands (SBs) play a critical role in determining the mechanical behavior of metallic glasses (MGs). However, the rapid dynamics and highly localized nature of SB propagation present significant challenges for direct observation of their atomistic mechanisms using experimental techniques. In this study, we employ hybrid molecular dynamics/Monte Carlo simulations to investigate the atomic-scale mechanisms of SB propagation in Mg₆₅Cu₂₅Y₁₀ MGs, prepared using cooling rates as slow as 10⁴ K s^-1-comparable to experimental casting conditions and significantly slower than the 10¹⁰ K s^-1 rates previously employed in atomistic simulations. Our results reveal a qualitative shift in SB propagation mechanisms as the struc2025-01-01T00:00:00Z2025 Jul2026-06-06T08:45:20.05Z2026-05-28T03:10:24.213ZS-EPMC122604374059159410.1073/pnas.2427082122