Atomistic modelling of thermal-cycling rejuvenation in metallic glasses

Cycling of a metallic glass between ambient and cryogenic temperatures can induce higher-energy states characteristic formation on faster cooling. This rejuvenation, unexpected because it occurs at small macroscopic strains well below the thermally induced structural change, is important, for example, in improving plasticity. Molecular-dynamics simulations elucidate mechanisms by which thermal cycling relaxation (reaching lower energy) as rejuvenation. Thermal cycling, over tens cycles, drives local atomic rearrangements progressively erasing initial structure. arises mainly from heating stage each cycle, linked to intrinsic heterogeneity glasses. Although, particular, timescales MD are shorter than physical experiments, present reproduce many physically observed effects, suggesting that they may be useful optimizing tuning properties glasses general.