The Effect of Creep Aging on the Fatigue Fracture Behavior of 2524 Aluminum Alloy
Abstract
:1. Introduction
2. Materials and Methods
3. Results and Discussion
3.1. Mechanical Properties
3.2. Fatigue Fracture Analysis
3.3. Microstructure
3.4. Discussion
4. Conclusions
- (1)
- Mechanical performance of samples after artificial aging and creep aging has enjoyed significant improvement over that of the T3 alloy. Fatigue life of the alloy through creep aging has also enjoyed improvement over that of the T3 alloy, and the fatigue life of samples after artificial aging treatment drops.
- (2)
- The fatigue fracture morphology of samples in three states is divided into the fatigue source area, the fatigue crack expansion area, and the instant fracture area. Among them, the morphological difference of the fatigue crack expansion area is the largest, fatigue striation of the creep aging alloy is relatively narrow, and there are micro cracks appearing at the fatigue striation of the artificial aging alloy.
- (3)
- All samples treated by artificial aging and creep aging precipitate S′ phases, about 60-nm PFZ appears at the crystal boundary of the samples treated by artificial aging, and the PFZ of the samples treated by creep aging is narrow or even absent.
- (4)
- Transgranular phase precipitation can improve the anti-plastic deformation ability of materials, hence raising the fatigue life of alloy. The presence of rough second phases and PFZ at the crystal boundary is likely to make the alloy crack at the boundary, lowering its fatigue life.
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Sample | Tensile Strength/MPa | Yield Strength/MPa | Elongation/% |
---|---|---|---|
T3 | 477.65 | 339.72 | 18.53 |
AA | 490.22 | 439.39 | 8.25 |
CA | 503.17 | 462.17 | 8.56 |
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Li, W.; Zhan, L.; Liu, L.; Xu, Y. The Effect of Creep Aging on the Fatigue Fracture Behavior of 2524 Aluminum Alloy. Metals 2016, 6, 215. https://doi.org/10.3390/met6090215
Li W, Zhan L, Liu L, Xu Y. The Effect of Creep Aging on the Fatigue Fracture Behavior of 2524 Aluminum Alloy. Metals. 2016; 6(9):215. https://doi.org/10.3390/met6090215
Chicago/Turabian StyleLi, Wenke, Lihua Zhan, Lingfeng Liu, and Yongqian Xu. 2016. "The Effect of Creep Aging on the Fatigue Fracture Behavior of 2524 Aluminum Alloy" Metals 6, no. 9: 215. https://doi.org/10.3390/met6090215