Intrinsic mechanical behavior of MgAgSb thermoelectric material: An ab initio study
α-MgAgSb based thermoelectric (TE) device attracts much attention for its commercial application because it shows an extremely high conversion efficiency of ∼8.5% under a temperature difference of 225 K. However, the mechanical behavior of α-MgAgSb is another serious consideration for its engineerin...
| Main Authors: | , , , , , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2020-03-01
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| Series: | Journal of Materiomics |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2352847819301236 |
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| author | Guodong Li Qi An Umut Aydemir Sergey I. Morozov Bo Duan Pengcheng Zhai Qingjie Zhang William A. Goddard, III |
| author_facet | Guodong Li Qi An Umut Aydemir Sergey I. Morozov Bo Duan Pengcheng Zhai Qingjie Zhang William A. Goddard, III |
| author_sort | Guodong Li |
| collection | DOAJ |
| description | α-MgAgSb based thermoelectric (TE) device attracts much attention for its commercial application because it shows an extremely high conversion efficiency of ∼8.5% under a temperature difference of 225 K. However, the mechanical behavior of α-MgAgSb is another serious consideration for its engineering applications. Here, we apply density functional theory (DFT) simulations to examine the intrinsic mechanical properties of all three MgAgSb phases, including elastic properties, shear-stress – shear-strain relationships, deformation and failure mechanism under ideal shear and biaxial shear conditions. We find that the ideal shear strength of α-MgAgSb is 3.25 GPa along the most plausible (100)<010> slip system. This strength is higher than that of β-MgAgSb (0.80 GPa) and lower than that of γ-MgAgSb (3.43 GPa). The failure of α-MgAgSb arises from the stretching and breakage of MgSb bond α-MgAgSb under pure shear load, while it arises from the softening of MgAg bond and the breakage of AgSb bond under biaxial shear load. This suggests that the deformation mechanism changes significantly under different loading conditions. Keywords: MgAgSb thermoelectric materials, Density functional theory, Ideal strength, Deformation mechanism |
| first_indexed | 2024-03-12T05:44:33Z |
| format | Article |
| id | doaj.art-7a928b6258774960997df9c324b100bb |
| institution | Directory Open Access Journal |
| issn | 2352-8478 |
| language | English |
| last_indexed | 2024-03-12T05:44:33Z |
| publishDate | 2020-03-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Materiomics |
| spelling | doaj.art-7a928b6258774960997df9c324b100bb2023-09-03T05:40:40ZengElsevierJournal of Materiomics2352-84782020-03-01612432Intrinsic mechanical behavior of MgAgSb thermoelectric material: An ab initio studyGuodong Li0Qi An1Umut Aydemir2Sergey I. Morozov3Bo Duan4Pengcheng Zhai5Qingjie Zhang6William A. Goddard, III7Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics, School of Science, Wuhan University of Technology, Wuhan, 430070, China; State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, 430070, China; Corresponding author. Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics, School of Science, Wuhan University of Technology, Wuhan, 430070, China.Department of Chemical and Materials Engineering, University of Nevada Reno, Reno, NV, 89557, USADepartment of Chemistry, Koç University, Sariyer, Istanbul, 34450, Turkey; Boron and Advanced Materials Research Center, Koç University, Sariyer, Istanbul, 34450, TurkeyDepartment of Computer Simulation and Nanotechnology, South Ural State University, Chelyabinsk, 454080, RussiaHubei Key Laboratory of Theory and Application of Advanced Materials Mechanics, School of Science, Wuhan University of Technology, Wuhan, 430070, ChinaHubei Key Laboratory of Theory and Application of Advanced Materials Mechanics, School of Science, Wuhan University of Technology, Wuhan, 430070, China; State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, 430070, China; Corresponding author. Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics, School of Science, Wuhan University of Technology, Wuhan, 430070, China.State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, 430070, ChinaMaterials and Process Simulation Center, California Institute of Technology, Pasadena, CA, 91125, USAα-MgAgSb based thermoelectric (TE) device attracts much attention for its commercial application because it shows an extremely high conversion efficiency of ∼8.5% under a temperature difference of 225 K. However, the mechanical behavior of α-MgAgSb is another serious consideration for its engineering applications. Here, we apply density functional theory (DFT) simulations to examine the intrinsic mechanical properties of all three MgAgSb phases, including elastic properties, shear-stress – shear-strain relationships, deformation and failure mechanism under ideal shear and biaxial shear conditions. We find that the ideal shear strength of α-MgAgSb is 3.25 GPa along the most plausible (100)<010> slip system. This strength is higher than that of β-MgAgSb (0.80 GPa) and lower than that of γ-MgAgSb (3.43 GPa). The failure of α-MgAgSb arises from the stretching and breakage of MgSb bond α-MgAgSb under pure shear load, while it arises from the softening of MgAg bond and the breakage of AgSb bond under biaxial shear load. This suggests that the deformation mechanism changes significantly under different loading conditions. Keywords: MgAgSb thermoelectric materials, Density functional theory, Ideal strength, Deformation mechanismhttp://www.sciencedirect.com/science/article/pii/S2352847819301236 |
| spellingShingle | Guodong Li Qi An Umut Aydemir Sergey I. Morozov Bo Duan Pengcheng Zhai Qingjie Zhang William A. Goddard, III Intrinsic mechanical behavior of MgAgSb thermoelectric material: An ab initio study Journal of Materiomics |
| title | Intrinsic mechanical behavior of MgAgSb thermoelectric material: An ab initio study |
| title_full | Intrinsic mechanical behavior of MgAgSb thermoelectric material: An ab initio study |
| title_fullStr | Intrinsic mechanical behavior of MgAgSb thermoelectric material: An ab initio study |
| title_full_unstemmed | Intrinsic mechanical behavior of MgAgSb thermoelectric material: An ab initio study |
| title_short | Intrinsic mechanical behavior of MgAgSb thermoelectric material: An ab initio study |
| title_sort | intrinsic mechanical behavior of mgagsb thermoelectric material an ab initio study |
| url | http://www.sciencedirect.com/science/article/pii/S2352847819301236 |
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