First-principles study of the ternary effects on the plasticity of $$\upgamma $$ γ -TiAl crystals
Abstract We studied the effects of important ternary elements, such as Cr, Nb, and V, on the plasticity of $$\upgamma $$ γ -TiAl crystals by calculating the point defect formation energy and the change in the generalized stacking fault energy (GSFE) surface from first-principles calculations. For al...
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Nature Portfolio
2020-12-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-020-77891-5 |
| _version_ | 1818429303981867008 |
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| author | Taegu Lee Seong-Woong Kim Ji Young Kim Won-Seok Ko Seunghwa Ryu |
| author_facet | Taegu Lee Seong-Woong Kim Ji Young Kim Won-Seok Ko Seunghwa Ryu |
| author_sort | Taegu Lee |
| collection | DOAJ |
| description | Abstract We studied the effects of important ternary elements, such as Cr, Nb, and V, on the plasticity of $$\upgamma $$ γ -TiAl crystals by calculating the point defect formation energy and the change in the generalized stacking fault energy (GSFE) surface from first-principles calculations. For all three elements, the point defect formation energies of the substitutional defects are lower in the Ti site than in the Al site, which implies that substitution on the Ti site is energetically more stable. We computed the GSFE surfaces with and without a substitutional solute and obtained the ideal critical resolved shear stress (ICRSS) of each partial slip. The change in the GSFE surface indicates that the substitution of Ti with Cr, Nb, or V results in an increase in the yield strength because the ICRSS of the superlattice intrinsic stacking fault (SISF) partial slip increases. Interestingly, we find that Cr substitution on an Al site could occur owing to the small difference between the substitutional defect formation energies of the Ti and Al sites. In that case, the reduction of ICRSSs of the SISF partial slip and twinning would lead to improved twinnability. We discuss the implications of the computational predictions by comparing them with experimental results in the literature. |
| first_indexed | 2024-12-14T15:15:23Z |
| format | Article |
| id | doaj.art-34cff43af22e4c67b36e77d144cfdb45 |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-12-14T15:15:23Z |
| publishDate | 2020-12-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-34cff43af22e4c67b36e77d144cfdb452022-12-21T22:56:21ZengNature PortfolioScientific Reports2045-23222020-12-0110111210.1038/s41598-020-77891-5First-principles study of the ternary effects on the plasticity of $$\upgamma $$ γ -TiAl crystalsTaegu Lee0Seong-Woong Kim1Ji Young Kim2Won-Seok Ko3Seunghwa Ryu4Department of Mechanical Engineering, Korea Advanced Institute of Science and TechnologyTitanium Department, Korea Institute of Materials ScienceTitanium Department, Korea Institute of Materials ScienceSchool of Materials Science and Engineering, University of UlsanDepartment of Mechanical Engineering, Korea Advanced Institute of Science and TechnologyAbstract We studied the effects of important ternary elements, such as Cr, Nb, and V, on the plasticity of $$\upgamma $$ γ -TiAl crystals by calculating the point defect formation energy and the change in the generalized stacking fault energy (GSFE) surface from first-principles calculations. For all three elements, the point defect formation energies of the substitutional defects are lower in the Ti site than in the Al site, which implies that substitution on the Ti site is energetically more stable. We computed the GSFE surfaces with and without a substitutional solute and obtained the ideal critical resolved shear stress (ICRSS) of each partial slip. The change in the GSFE surface indicates that the substitution of Ti with Cr, Nb, or V results in an increase in the yield strength because the ICRSS of the superlattice intrinsic stacking fault (SISF) partial slip increases. Interestingly, we find that Cr substitution on an Al site could occur owing to the small difference between the substitutional defect formation energies of the Ti and Al sites. In that case, the reduction of ICRSSs of the SISF partial slip and twinning would lead to improved twinnability. We discuss the implications of the computational predictions by comparing them with experimental results in the literature.https://doi.org/10.1038/s41598-020-77891-5 |
| spellingShingle | Taegu Lee Seong-Woong Kim Ji Young Kim Won-Seok Ko Seunghwa Ryu First-principles study of the ternary effects on the plasticity of $$\upgamma $$ γ -TiAl crystals Scientific Reports |
| title | First-principles study of the ternary effects on the plasticity of $$\upgamma $$ γ -TiAl crystals |
| title_full | First-principles study of the ternary effects on the plasticity of $$\upgamma $$ γ -TiAl crystals |
| title_fullStr | First-principles study of the ternary effects on the plasticity of $$\upgamma $$ γ -TiAl crystals |
| title_full_unstemmed | First-principles study of the ternary effects on the plasticity of $$\upgamma $$ γ -TiAl crystals |
| title_short | First-principles study of the ternary effects on the plasticity of $$\upgamma $$ γ -TiAl crystals |
| title_sort | first principles study of the ternary effects on the plasticity of upgamma γ tial crystals |
| url | https://doi.org/10.1038/s41598-020-77891-5 |
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