کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1644811 | 1517273 | 2014 | 4 صفحه PDF | دانلود رایگان |
• Tetragonal transition of TiHx is divided into two types in terms of energy pathway.
• The intrinsic composition range of the δ→ε transition is 1.5≤x≤2.
• Mechanical instability causes δ→ε and internal symmetry breaking induces δ→γ.
• Poisson ratio of δ phases between x and z axes is proposed for tetragonal transitions.
• The present results could clarify the controversies about tetragonal transitions.
First principles calculation reveals that the tetragonal transitions of TiHx (1≤x≤2) could be divided into two types in terms of energy pathway, and that the intrinsic composition range of the δ→ε transition is 1.5≤x≤2. Calculation also indicates that the fundamental reasons for the δ→ε and δ→γ transitions are quite different from each other, i.e., mechanical instability causes the δ→ε transition and internal symmetry breaking of cubic structures induces the δ→γ transition. In addition, the Poisson ratio of δ phases between the x and z axes is proposed to provide a deeper understanding of intrinsic natures of tetragonal transitions.
Journal: Materials Letters - Volume 115, 15 January 2014, Pages 252–255