Energy paths of twin-related lattice reorientation in hexagonal metals via ab initio calculations

• DOI: 10.1016/j.jmst.2017.09.009
• Publication Date: 2017-09-06T21:50:40Z
• Authors: Gang Zhou; Lihua Ye; Hao Wang; Dongsheng Xu; Changgong Meng; Rui Yang
• Keywords: Lattice (music); Total energy; Hexagonal Lattice

Employing ab initio calculations, we systematically investigated the energy paths of [10 (1) over bar2] twin-related lattice reorientation in hexagonal metals Be, Mg, Sc, Ti, Co, Y, Zr, Tc, Ru, Gd, Tb, Dy, Ho, Er, Tm, Lu, Hf, Re, and Os. Among the studied systems, lattice reorientation energy increases in the order of Mg, Gd, Tb, Dy, Zr, Tc, Ti, Ho, Y, Co, Er, Sc, Be, Tm, Lu, Hf, Re, Ru and Os. The reorientation process consists of shear and shuffle components. Concerning the significance of shuffle, these hexagonal metals fall into two groups. In the first group, which includes Mg, Co, Ru, Re and Os, regardless of the shear amount, subsequent shuffle is an energy-uphill process, while in the second group, which includes Ti, Tc, Be, Y, Gd, Tb, Dy, Ho, Zr, Er, Sc, Hf, Lu and Tm, shuffle becomes an energy-downhill process if shear component reaches an adequate level (at least 60%). These results qualitatively explain the present observation of lattice reorientation in hexagonal metals, and shed light upon a general understanding on the [10 (1) over bar2] twinning behavior in the aim of improving materials properties. (C) 2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.