Effect of Sc on the microstructure and room-temperature mechanical properties of Nb-Si based alloys
The microstructure and room-temperature mechanical properties of directionally solidified and heat-treated Nb‑16Si‑23Ti‑4Cr‑2Al‑2Hf‑0/0.3/0.5Sc (at.%) alloys were investigated. All alloys consisted of Nb-based solid solution (Nbss), α‑Nb5Si3 and γ‑Nb5Si3 with preferred 〈001〉 orientation for the firs...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2018-12-01
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| Series: | Materials & Design |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S0264127518307561 |
| _version_ | 1831752611959668736 |
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| author | Yonglin Huang Lina Jia Zuheng Jin Bin Kong Yueling Guo Jiangbo Sha Hu Zhang |
| author_facet | Yonglin Huang Lina Jia Zuheng Jin Bin Kong Yueling Guo Jiangbo Sha Hu Zhang |
| author_sort | Yonglin Huang |
| collection | DOAJ |
| description | The microstructure and room-temperature mechanical properties of directionally solidified and heat-treated Nb‑16Si‑23Ti‑4Cr‑2Al‑2Hf‑0/0.3/0.5Sc (at.%) alloys were investigated. All alloys consisted of Nb-based solid solution (Nbss), α‑Nb5Si3 and γ‑Nb5Si3 with preferred 〈001〉 orientation for the first two phases, and Sc was enriched in γ‑Nb5Si3 phase. Sc-added alloys showed a more continuous Nbss matrix in which the finer Nb5Si3 phase distributed uniformly. The volume fraction of both α‑Nb5Si3 and γ‑Nb5Si3 phase was decreased by Sc addition. Sc alloying reduced the Young's modulus and nano-hardness of Nbss phase. 0.50 at.% Sc addition enhanced the fracture toughness and tensile strength from 9.88 MPa m1/2 and 430.3 MPa to 25.95 MPa m1/2 and 1119.7 MPa. The improvement in fracture toughness was due to the better deformability of Nbss phase. The high tensile strength was attributed to the dispersed and refined Nb5Si3 phase, which was not degraded by the increased Nbss volume fraction since dislocations were not open within most Nbss phase. Besides, the strong interface cohesion was preferable for the strength of Sc-added alloys. Keywords: Microstructure, Growth orientation, Young's modulus, Nano-hardness, Fracture toughness, Tensile strength |
| first_indexed | 2024-12-21T23:06:21Z |
| format | Article |
| id | doaj.art-c3920c638a6e4be5b74c57bf0d4a644f |
| institution | Directory Open Access Journal |
| issn | 0264-1275 |
| language | English |
| last_indexed | 2024-12-21T23:06:21Z |
| publishDate | 2018-12-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Materials & Design |
| spelling | doaj.art-c3920c638a6e4be5b74c57bf0d4a644f2022-12-21T18:47:09ZengElsevierMaterials & Design0264-12752018-12-01160671682Effect of Sc on the microstructure and room-temperature mechanical properties of Nb-Si based alloysYonglin Huang0Lina Jia1Zuheng Jin2Bin Kong3Yueling Guo4Jiangbo Sha5Hu Zhang6School of Materials Science and Engineering, Beihang University, Beijing 100191, ChinaCorresponding author.; School of Materials Science and Engineering, Beihang University, Beijing 100191, ChinaSchool of Materials Science and Engineering, Beihang University, Beijing 100191, ChinaSchool of Materials Science and Engineering, Beihang University, Beijing 100191, ChinaSchool of Materials Science and Engineering, Beihang University, Beijing 100191, ChinaSchool of Materials Science and Engineering, Beihang University, Beijing 100191, ChinaSchool of Materials Science and Engineering, Beihang University, Beijing 100191, ChinaThe microstructure and room-temperature mechanical properties of directionally solidified and heat-treated Nb‑16Si‑23Ti‑4Cr‑2Al‑2Hf‑0/0.3/0.5Sc (at.%) alloys were investigated. All alloys consisted of Nb-based solid solution (Nbss), α‑Nb5Si3 and γ‑Nb5Si3 with preferred 〈001〉 orientation for the first two phases, and Sc was enriched in γ‑Nb5Si3 phase. Sc-added alloys showed a more continuous Nbss matrix in which the finer Nb5Si3 phase distributed uniformly. The volume fraction of both α‑Nb5Si3 and γ‑Nb5Si3 phase was decreased by Sc addition. Sc alloying reduced the Young's modulus and nano-hardness of Nbss phase. 0.50 at.% Sc addition enhanced the fracture toughness and tensile strength from 9.88 MPa m1/2 and 430.3 MPa to 25.95 MPa m1/2 and 1119.7 MPa. The improvement in fracture toughness was due to the better deformability of Nbss phase. The high tensile strength was attributed to the dispersed and refined Nb5Si3 phase, which was not degraded by the increased Nbss volume fraction since dislocations were not open within most Nbss phase. Besides, the strong interface cohesion was preferable for the strength of Sc-added alloys. Keywords: Microstructure, Growth orientation, Young's modulus, Nano-hardness, Fracture toughness, Tensile strengthhttp://www.sciencedirect.com/science/article/pii/S0264127518307561 |
| spellingShingle | Yonglin Huang Lina Jia Zuheng Jin Bin Kong Yueling Guo Jiangbo Sha Hu Zhang Effect of Sc on the microstructure and room-temperature mechanical properties of Nb-Si based alloys Materials & Design |
| title | Effect of Sc on the microstructure and room-temperature mechanical properties of Nb-Si based alloys |
| title_full | Effect of Sc on the microstructure and room-temperature mechanical properties of Nb-Si based alloys |
| title_fullStr | Effect of Sc on the microstructure and room-temperature mechanical properties of Nb-Si based alloys |
| title_full_unstemmed | Effect of Sc on the microstructure and room-temperature mechanical properties of Nb-Si based alloys |
| title_short | Effect of Sc on the microstructure and room-temperature mechanical properties of Nb-Si based alloys |
| title_sort | effect of sc on the microstructure and room temperature mechanical properties of nb si based alloys |
| url | http://www.sciencedirect.com/science/article/pii/S0264127518307561 |
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