A 12R long-period stacking-ordered structure in a Mg-Ni-Y alloy

作者：Liu, Cheng; Zhu, Yuman; Luo, Qun; Liu, Bin; Gu, Qinfen; Li, Qian^*

来源：Journal of Materials Science & Technology, 2018, 34(12): 2235-2239.

DOI：10.1016/j.jmst.2018.06.015

• Mg alloys
• LPSO
• HAADF-STEM
• Crystal structure

A hitherto unreported long-period stacking-ordered (LPSO) phase, designated 12R, was observed in a Mg80Ni5Y15 (at.%) alloy. Microstructure was investigated by electron diffraction and high-angle annular dark-field scanning transmission electron microscopy. Results show that the 12R has a trigonal lattice (a = b = 1.112 nm, c = 3.126 nm, alpha = beta = 90 degrees, and gamma = 120 degrees). Unit cell of the 12R is consisted of three ABCA-type building blocks and each building block contains dominant Ni6Y8-type building clusters. A sound structural model is proposed based on relative positions of Ni(6)y(8) clusters in neighboring building blocks.

• 出版日期2018-12
• 单位上海大学; 上海材料研究所