Microstructurally based cross-slip mechanisms and their effects on dislocation microstructure evolution in fcc crystals
نویسندگان
چکیده
Three newly identified cross-slip mechanisms from atomistic simulations of fcc crystals, namely surface, bulk and intersection cross-slip types, were hierarchically informed into discrete dislocation dynamics simulations. The influence of each cross-slip type on the evolution of the dislocation microstructure in face-centered cubic microcrystals having different crystal sizes and initial dislocation densities was investigated. Dislocation pattern formation, surface slip localization and initial strain hardening were observed, in agreement with experimental observations, and possible explanations are given in the light of these simulations. 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
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