Origin of profuse {11(2)over-bar1} deformation twins in Mg-Gd alloys

SCRIPTA MATERIALIA

卷:191

Article

He, Cong¹  Li, Zhigiao¹  Kong, Dehao¹  Zhao, Xiaojun¹  Chen, Houwen^1,2,3  Nie, Jian-Feng⁴ 

[1] Chongqing Univ, Coll Mat Sci & Engn, Int Joint Lab Light Alloys, Minist Educ, Chongqing 400044, Peoples R China

[2] Chongqing Univ, Shenyang Natl Lab Mat Sci, Chongqing 400044, Peoples R China

[3] Chongqing Univ, Electron Microscopy Ctr, Chongqing 400044, Peoples R China

[4] Monash Univ, Dept Mat Sci & Engn, Clayton, Vic 3800, Australia

关键词: Deformation twins;    Mg alloys;    Twin boundary;    First-principles calculations;   

DOI  :  10.1016/j.scriptamat.2020.08.041

来源: Elsevier

【 摘 要 】

Deformation twins in Mg-Gd alloys are investigated. It is found that the dominant twinning mode switches from {10 (1) over bar2} twinning to {11 (2) over bar1} twinning, with an increase in the Gd concentration in Mg. Our first-principles calculations suggest that the formation of the {11 (2) over bar1} twin in the Gd-rich alloy is triggered by the reduced {11 (2) over bar1} twin boundary energy, which results from strain relaxation along the twin boundary. Furthermore, this twinning mode is suggestive to be activated in other Mg alloys with a high concentration of solute atoms having larger size than Mg. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

Free