A Microstructural Evaluation of Friction Stir Welded 7075 Aluminum Rolled Plate Heat Treated to the Semi-Solid State
Abstract
:1. Introduction
2. Materials and Methods
3. Results and Discussion
3.1. Microstructural Evolution of the Friction Stir Welded Plates
3.2. Post Welding Heat Treatment
3.3. Vickers Hardness Results
4. Conclusions
- (a)
- The base metal consists of typical pancake-shaped grains elongated in the rolling direction but the grain size is significantly decreased in the nugget zone due to extensive plastic deformation that the materials undergo during FSW;
- (b)
- Grains start to grow throughout the material during heat treatment at 628 °C, resulting in uniform non-dendritic microstructures similar to those obtained by thixoforming;
- (c)
- Hardness tests show that hardness in the NZ is higher than that in TMAZ and BM due to the ultra-fine grain structure attained in this area.
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Alloy | Cu | Zn | Mg | Mn | Cr | Ti | Si | Fe | Zr | B | Al |
---|---|---|---|---|---|---|---|---|---|---|---|
7075 | 0.94 | 4.52 | 2.24 | <0.01 | 0.22 | 0.05 | 0.02 | <0.01 | <0.01 | <0.01 | Bal. |
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Azadi Chegeni, A.; Kapranos, P. A Microstructural Evaluation of Friction Stir Welded 7075 Aluminum Rolled Plate Heat Treated to the Semi-Solid State. Metals 2018, 8, 41. https://doi.org/10.3390/met8010041
Azadi Chegeni A, Kapranos P. A Microstructural Evaluation of Friction Stir Welded 7075 Aluminum Rolled Plate Heat Treated to the Semi-Solid State. Metals. 2018; 8(1):41. https://doi.org/10.3390/met8010041
Chicago/Turabian StyleAzadi Chegeni, Ava, and Platon Kapranos. 2018. "A Microstructural Evaluation of Friction Stir Welded 7075 Aluminum Rolled Plate Heat Treated to the Semi-Solid State" Metals 8, no. 1: 41. https://doi.org/10.3390/met8010041