Atomic-scale observation of dynamic grain boundary structural transformation during shear-mediated migration.

ABSTRACT: Grain boundary (GB) structural change is commonly observed during and after stress-driven GB migration in nanocrystalline materials, but its exact atomic scale transformation has not been explored experimentally. Here, using in situ high-resolution transmission electron microscopy combined with molecular dynamics simulations, we observed the dynamic GB structural transformation stemming from reversible facet transformation and GB dissociation during the shear-mediated migration of faceted GBs in gold nanocrystals. A reversible transformation was found to occur between (002)/(111) and Σ11(113) GB facets, accomplished by the coalescence and detachment of [Formula: see text]-type GB steps or disconnections that mediated the GB migration. In comparison, the dissociation of (002)/(111) GB into

SUBMITTER: Fang Z 

PROVIDER: S-EPMC9651741 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature