Nanoscale precipitates as sustainable dislocation sources for enhanced ductility and high strength.

ABSTRACT: Traditionally, precipitates in a material are thought to serve as obstacles to dislocation glide and cause hardening of the material. This conventional wisdom, however, fails to explain recent discoveries of ultrahigh-strength and large-ductility materials with a high density of nanoscale precipitates, as obstacles to dislocation glide often lead to high stress concentration and even microcracks, a cause of progressive strain localization and the origin of the strength-ductility conflict. Here we reveal that nanoprecipitates provide a unique type of sustainable dislocation sources at sufficiently high stress, and that a dense dispersion of nanoprecipitates simultaneously serve as dislocation sources and obstacles, leading to a sustainable and self-hardening deformation mechanism for enhanc

SUBMITTER: Peng S 

PROVIDER: S-EPMC7071881 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature