Orientation influence on grain size effects in ultrafine-grained magnesium

SCRIPTA MATERIALIA

卷:97

Article

Fan, Haidong^1,2  Aubry, Sylvie³  Arsenlis, A.³  El-Awady, Jaafar A.¹ 

[1] Johns Hopkins Univ, Dept Mech Engn, Baltimore, MD 21218 USA

[2] Sichuan Univ, Dept Mech, Chengdu 610065, Sichuan, Peoples R China

[3] Lawrence Livermore Natl Lab, Condensed Matter & Mat Div, Livermore, CA 94551 USA

关键词: Discrete dislocation dynamics;    Grain size effects;    Ultrafine-grained magnesium;    Orientation;   

DOI  :  10.1016/j.scriptamat.2014.10.031

来源: Elsevier

【 摘 要 】

The mechanical behavior of ultrafine-grained magnesium was studied by discrete dislocation dynamics (DDD) simulations. Our results show basal slip yields a strong size effect, while prismatic and pyramidal slips produce a weak one. We developed a new size strength model that considers dislocation transmission across grain boundaries. Good agreement between this model, current DDD simulations and previous experiments was observed. These results reveal that the grain size effect depends on three factors: Peierls stress, dislocation source strength and grain boundary strength. (C) 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

Free