Strain self-accommodation during growth of 14H type long-period stacking ordered (LPSO) structures in Mg-Zn-Gd alloy

SCRIPTA MATERIALIA

卷:185

Article

Gu, Xin-Fu^1,2  Furuhara, Tadashi²  Kiguchi, Takanori²  Konno, Toyohiko J.²  Chen, Leng¹  Yang, Ping¹ 

[1] Univ Sci & Technol Beijing, Sch Mat Sci & Engn, 30 Xueyuan Rd, Beijing 100083, Peoples R China

[2] Tohoku Univ, Inst Mat Res, Sendai, Miyagi 9808577, Japan

关键词: Magnesium alloy;    Strain accommodation;    Scanning Transmission Electron Microscopy (STEM);    Dislocation structure;    Modeling;   

DOI  :  10.1016/j.scriptamat.2020.04.009

来源: Elsevier

【 摘 要 】

Cooperative growth of the structure units (SUs) in a 14H type long-period stacking ordered (LPSO) structure has been observed, and there is no obvious accumulation of transformation strain at the growth fronts. The atomic structures at this front are further characterized by Cs-corrected scanning transmission electron microscopy, and the partial dislocations associated SUs are uniquely defined based on the observations at different zone axes. It is found that the Burgers vectors of neighbouring partials are alternatively opposed so that the transformation strain is self-accommodated. Furthermore, this self-accommodation mechanism is rationalized by the elastic interaction energy for combinations of different partials. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

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