Heterogeneous deformation of friction stir welded aluminum alloy 6061 in tension and high cycle fatigue
International Journal of Structural Integrity
ISSN: 1757-9864
Article publication date: 21 July 2022
Issue publication date: 12 September 2022
Abstract
Purpose
The investigations provide a basis for the optimization of the alloy 6061-T6 friction stir welding (FSW) process to improve the mechanical properties of welded joints.
Design/methodology/approach
The local deformation of the FSW joint in tension and fatigue test were experimentally investigated by digital image correlation (DIC) technique.
Findings
The local stress-strain behaviors of the sub-regions show that the plastic strain always concentrated at the heat affected zone (HAZ) on the advancing side both in tension and high cycle fatigue and eventually leads to the final fracture. The evolution of the plastic strain at very low stress is extremely slow and accounts for most of the total fatigue life. However, the local deformation exhibits a sudden increase just before the fatigue failure.
Originality/value
Based on the experimental data, the result indicates that the HAZ is the weakest zone across the weld and the strain localization in high cycle fatigue is very harmful and unpredictable for the FSW joints.
Keywords
Acknowledgements
This research was financially supported by the National Natural Science Foundation of China (Grant number 12072212) and the Sichuan Science and Technology Program (2021YJ0071 and 2020YJ0230). Special thanks to Dr. Yan Li from the Department of Mechanics, Sichuan University.
Citation
Dai, Y., Liu, C., Zhan, M., Wang, X., He, C. and Wang, Q. (2022), "Heterogeneous deformation of friction stir welded aluminum alloy 6061 in tension and high cycle fatigue", International Journal of Structural Integrity, Vol. 13 No. 5, pp. 813-828. https://doi.org/10.1108/IJSI-06-2022-0079
Publisher
:Emerald Publishing Limited
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