TY - JOUR A1 - Maaß, Robert A1 - Derlet, P. T1 - Micro-plasticity in a fragile model binary glass T2 - Acta Materialia N2 - Atomistic deformation simulations in the nominally elastic regime are performed for a model binary glass with strain rates as low as 10 4 /s (corresponding to 0.01 shear strain per 1 μs). A strain rate dependent elastic softening due to a micro-plasticity is observed, which is mediated by thermally-activated localized structural transformations (LSEs). A closer inspection of the atomic-scale structure indicates the material response is distinctly different for two types of local atomic environments. A system spanning iscosahe- drally coordinated substructure responds purely elastically, whereas the remaining substructure admits both elastic and microplastic evolution. This leads to a heterogeneous internal stress distribution which, upon unloading, results in negative creep and complete residual-strain recovery. A detailed structural analysis in terms of local stress, atomic displacement, and SU(2) local bonding topology shows such mi- croscopic processes can result in large changes in local stress and are more likely to occur in geomet- rically frustrated regions characterized by higher free volume and softer elastic stiffness. The thermally- activated LSE activity also mediates structural relaxation, and in this way should be distinguished from stress-driven shear transformation activity which only rejuvenates glass structure. The frequency of LSE activity, and therefore the amount of micro-plasticity, is found to be related to the degree to which the glassy state is relaxed. These insights shed atomistic light onto the structural origins that may govern re- cent experimental observations of significant structural evolution in response to elastic loading protocols. PB - Elsevier Ltd. KW - Molecular dynamics KW - Bulk metallic glasses KW - Plasticity KW - Residual strains PY - 2021 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/52378 AN - OPUS4-52378 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-523782 VL - 209 SP - 116771 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany