Mechanical and electronic properties of A1−xBxHy (A and B=Ti, Zr, Hf) hydride alloys: A first-principles study
| Autor: | Yunya Dai, Wenzeng Bing, Kaimin Fan, Xiaosong Zhou, Xinggui Long, Xiaotao Zu, Fei Gao, Li Yang, JL Nie, Shuming Peng |
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| Rok vydání: | 2013 |
| Předmět: |
Materials science
Hydride Mechanical Engineering Fermi level Metals and Alloys Ab initio Electronic structure symbols.namesake Tetragonal crystal system Mechanics of Materials Computational chemistry Ab initio quantum chemistry methods Materials Chemistry symbols Density of states Physical chemistry Ternary operation |
| Zdroj: | Journal of Alloys and Compounds. 581:404-412 |
| ISSN: | 0925-8388 |
| Popis: | Using ab initio calculations, we investigated the mechanical and electronic properties of Ti1−xHfxHy, Ti1−xZrxHy and Zr1−xHfxTHy (x = 0, 0.25, 0.5, 0.75, 1; y = 1.5, 1.75, 2). The calculated results in binary hydrides show that the β-phase MH1.5[1 0 0] (M = Ti, Zr, Hf) are more stable than other possible structures. At the Fermi level, the density of states for metal d state increases with increasing the H concentration in MHy (y ranged from 1.5 to 2), which leads to the instability of their fcc structures and induces the tetragonal distortion. Ti0.75Hf0.25H1.5 and Zr0.25Hf0.75H1.5 exhibit the highest mechanical stability, while Ti0.25Zr0.75H1.5 has the lowest mechanical stability among the corresponding ternary systems considered. Moreover, the systems studied in the present work are all anisotropic and show a ductile behavior. The tetragonal distortion in Ti1−xHfxH1.5, Ti1−xZrxH1.5 and Zr1−xHfxH1.5 is not observed, retaining their fcc structures. The electronic structure of A1−xBxHy (A and B = Ti, Hf, Zr) exhibits metallic character. |
| Databáze: | OpenAIRE |
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