Simultaneously increased strength and plasticity of TIG-welded 7075-T6 aluminum alloy joints via a novel post-weld composite treatment process
The 7075-T6 aluminum (Al) alloy is a high-strength material with great application potential. However, the tensile strength and elongation of its arc-welded joints are severely reduced compared to the base metal (BM), with only 57.3% and 14.4% of the BM values, respectively. To improve both strength...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2023-09-01
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| Series: | Journal of Materials Research and Technology |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S223878542301757X |
| _version_ | 1797646752920109056 |
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| author | Zejie Wang Zhaodong Zhang Jiwen Cheng Gang Song Liming Liu |
| author_facet | Zejie Wang Zhaodong Zhang Jiwen Cheng Gang Song Liming Liu |
| author_sort | Zejie Wang |
| collection | DOAJ |
| description | The 7075-T6 aluminum (Al) alloy is a high-strength material with great application potential. However, the tensile strength and elongation of its arc-welded joints are severely reduced compared to the base metal (BM), with only 57.3% and 14.4% of the BM values, respectively. To improve both strength and plasticity simultaneously, a novel post-weld composite treatment process combining solution treatment, partial rolling, and natural aging treatment (SRA) was proposed. The SRA process enhanced the strength and elongation of welded joints to 84.5% and 83.1% of the BM, respectively. In different regions of the joints, the SRA process involved different strengthening mechanisms, including stronger work hardening in Region I, η′ phase precipitation and weaker work hardening in Region II, and refinement of the η’ and η phase in Region III. The SRA process also improved the formability of the welded joints from 62.5% to 87.5% of the BM. In addition, the SRA process increased the median fatigue life of welded joints by a factor of approximately 2–6. This was achieved by increasing the strength and microhardness of the fusion zone, which, in turn, reduced the number of fatigue crack sources and shifted crack sources from the surface to subsurface regions. |
| first_indexed | 2024-03-11T15:07:19Z |
| format | Article |
| id | doaj.art-e8b49cbf4b274d82b14ed3fa90f8973e |
| institution | Directory Open Access Journal |
| issn | 2238-7854 |
| language | English |
| last_indexed | 2024-03-11T15:07:19Z |
| publishDate | 2023-09-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Materials Research and Technology |
| spelling | doaj.art-e8b49cbf4b274d82b14ed3fa90f8973e2023-10-30T06:02:51ZengElsevierJournal of Materials Research and Technology2238-78542023-09-0126542555Simultaneously increased strength and plasticity of TIG-welded 7075-T6 aluminum alloy joints via a novel post-weld composite treatment processZejie Wang0Zhaodong Zhang1Jiwen Cheng2Gang Song3Liming Liu4Key Laboratory of Liaoning Advanced Welding and Joining Technology, School of Material Science and Engineering, Dalian University of Technology, Dalian, ChinaKey Laboratory of Liaoning Advanced Welding and Joining Technology, School of Material Science and Engineering, Dalian University of Technology, Dalian, ChinaKey Laboratory of Liaoning Advanced Welding and Joining Technology, School of Material Science and Engineering, Dalian University of Technology, Dalian, ChinaCorresponding author. 2 Ling Gong Road, Dalian, 116024, China.; Key Laboratory of Liaoning Advanced Welding and Joining Technology, School of Material Science and Engineering, Dalian University of Technology, Dalian, ChinaKey Laboratory of Liaoning Advanced Welding and Joining Technology, School of Material Science and Engineering, Dalian University of Technology, Dalian, ChinaThe 7075-T6 aluminum (Al) alloy is a high-strength material with great application potential. However, the tensile strength and elongation of its arc-welded joints are severely reduced compared to the base metal (BM), with only 57.3% and 14.4% of the BM values, respectively. To improve both strength and plasticity simultaneously, a novel post-weld composite treatment process combining solution treatment, partial rolling, and natural aging treatment (SRA) was proposed. The SRA process enhanced the strength and elongation of welded joints to 84.5% and 83.1% of the BM, respectively. In different regions of the joints, the SRA process involved different strengthening mechanisms, including stronger work hardening in Region I, η′ phase precipitation and weaker work hardening in Region II, and refinement of the η’ and η phase in Region III. The SRA process also improved the formability of the welded joints from 62.5% to 87.5% of the BM. In addition, the SRA process increased the median fatigue life of welded joints by a factor of approximately 2–6. This was achieved by increasing the strength and microhardness of the fusion zone, which, in turn, reduced the number of fatigue crack sources and shifted crack sources from the surface to subsurface regions.http://www.sciencedirect.com/science/article/pii/S223878542301757X7075-T6 aluminum alloyTIG weldingPost-weld treatmentMechanical propertiesStrengthening mechanism |
| spellingShingle | Zejie Wang Zhaodong Zhang Jiwen Cheng Gang Song Liming Liu Simultaneously increased strength and plasticity of TIG-welded 7075-T6 aluminum alloy joints via a novel post-weld composite treatment process Journal of Materials Research and Technology 7075-T6 aluminum alloy TIG welding Post-weld treatment Mechanical properties Strengthening mechanism |
| title | Simultaneously increased strength and plasticity of TIG-welded 7075-T6 aluminum alloy joints via a novel post-weld composite treatment process |
| title_full | Simultaneously increased strength and plasticity of TIG-welded 7075-T6 aluminum alloy joints via a novel post-weld composite treatment process |
| title_fullStr | Simultaneously increased strength and plasticity of TIG-welded 7075-T6 aluminum alloy joints via a novel post-weld composite treatment process |
| title_full_unstemmed | Simultaneously increased strength and plasticity of TIG-welded 7075-T6 aluminum alloy joints via a novel post-weld composite treatment process |
| title_short | Simultaneously increased strength and plasticity of TIG-welded 7075-T6 aluminum alloy joints via a novel post-weld composite treatment process |
| title_sort | simultaneously increased strength and plasticity of tig welded 7075 t6 aluminum alloy joints via a novel post weld composite treatment process |
| topic | 7075-T6 aluminum alloy TIG welding Post-weld treatment Mechanical properties Strengthening mechanism |
| url | http://www.sciencedirect.com/science/article/pii/S223878542301757X |
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