Ultra-high cycle fatigue and ultra-slow crack growth behavior of additively manufactured AlSi7Mg alloy
International Journal of Structural Integrity
ISSN: 1757-9864
Article publication date: 6 March 2024
Issue publication date: 8 April 2024
Abstract
Purpose
The purpose of this paper is to determine the ultra-high cycle fatigue behavior and ultra-slow crack propagation behavior of selective laser melting (SLM) AlSi7Mg alloy under as-built conditions.
Design/methodology/approach
Constant amplitude and two-step variable amplitude fatigue tests were carried out using ultrasonic fatigue equipment. The fracture surface of the failure specimen was quantitatively analyzed by scanning electron microscope (SEM).
Findings
The results show that the competition of surface and interior crack initiation modes leads to a duplex S–N curve. Both manufacturing defects (such as the lack of fusion) and inclusions can act as initially fatal fatigue microcracks, and the fatigue sensitivity level decreases with the location, size and type of the maximum defects.
Originality/value
The research results play a certain role in understanding the ultra-high cycle fatigue behavior of additive manufacturing aluminum alloys. It can provide reference for improving the process parameters of SLM technology.
Keywords
Acknowledgements
Acknowledgments are given to the National Natural Science Foundation of China (No. 12202080, No. 12332012, No. 11832007, No. 12102280) for the support and funding of the research project. Acknowledgments are given to the Key Laboratory of Deep Earth Science and Engineering of Sichuan University (No. DESE 202207) for providing experimental equipment and technical support for the research. Moreover, Dr Kun Yang highly appreciates the support from the Expert Service center of Human Resources and Social Security Department of Sichuan Province.
Citation
Zhao, Q., Li, X., Hu, J., Jiang, Y., Yang, K. and Wang, Q. (2024), "Ultra-high cycle fatigue and ultra-slow crack growth behavior of additively manufactured AlSi7Mg alloy", International Journal of Structural Integrity, Vol. 15 No. 2, pp. 382-407. https://doi.org/10.1108/IJSI-01-2024-0001
Publisher
:Emerald Publishing Limited
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