Microstructure of long period stacking ordered phase in an as-cast Mg-Ni-Zn-Dy alloy

Yuanlin Zhuang; Li Ye; Shengbo Gao; Xiaoqing Liu; Dongshan Zhao; Shuangfeng Jia; Jianian Gui; Jianbo Wang

doi:10.1016/j.micron.2019.04.007

Microstructure of long period stacking ordered phase in an as-cast Mg-Ni-Zn-Dy alloy

Micron. 2019 Jul:122:41-45. doi: 10.1016/j.micron.2019.04.007. Epub 2019 Apr 29.

Authors

Yuanlin Zhuang¹, Li Ye², Shengbo Gao¹, Xiaoqing Liu¹, Dongshan Zhao³, Shuangfeng Jia⁴, Jianian Gui¹, Jianbo Wang⁵

Affiliations

¹ School of Physics and Technology, Center for Electron Microscopy, MOE Key Laboratory of Artificial Micro- and Nano-structures, and Institute for Advanced Studies, Wuhan University, Wuhan, 430072, China.
² School of Physics and Technology, Center for Electron Microscopy, MOE Key Laboratory of Artificial Micro- and Nano-structures, and Institute for Advanced Studies, Wuhan University, Wuhan, 430072, China; School of Physical Engineering, Zhengzhou University, Zhengzhou, 450052, China.
³ School of Physics and Technology, Center for Electron Microscopy, MOE Key Laboratory of Artificial Micro- and Nano-structures, and Institute for Advanced Studies, Wuhan University, Wuhan, 430072, China. Electronic address: dszhao@whu.edu.cn.
⁴ School of Physics and Technology, Center for Electron Microscopy, MOE Key Laboratory of Artificial Micro- and Nano-structures, and Institute for Advanced Studies, Wuhan University, Wuhan, 430072, China. Electronic address: sfjia@whu.edu.cn.
⁵ School of Physics and Technology, Center for Electron Microscopy, MOE Key Laboratory of Artificial Micro- and Nano-structures, and Institute for Advanced Studies, Wuhan University, Wuhan, 430072, China; Science and Technology on High Strength Structural Materials Laboratory, Central South University, Changsha, 410083, China.

PMID: 31077908
DOI: 10.1016/j.micron.2019.04.007

Abstract

An as-cast Mg-5Ni-4Zn-1Dy (wt.%) alloy was prepared by traditional ingot metallurgy. Transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) were used to study the microstructural characteristics of 14H LPSO phase in the as-cast Mg-5Ni-4Zn-1Dy (wt.%) alloy. Selected-area electron diffraction, convergent-beam electron diffraction, energy dispersive spectrum and high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM) and atomic-resolution energy dispersive spectrum (EDS) mapping were used to study the microscopic characteristics of the 14H LPSO phase. The unit cell of 14H LPSO phase has two ABCA-type building blocks and the Zn, Ni and Dy elements were enriched on the ABCA-type stacking sequence, especially on the B and C layers. Space group of the 14H LPSO phase was determined to be P6₃mc and atomic structural model was constructed.

Keywords: Alloys; Convergent-beam electron diffraction; Crystal symmetry; Long-period stacking-ordered; Magnesium; Phases.