Research on fatigue curve fitting methods based on the notch stress approach
International Journal of Structural Integrity
ISSN: 1757-9864
Article publication date: 9 January 2024
Issue publication date: 8 April 2024
Abstract
Purpose
This study investigates the fitting techniques for notch fatigue curves, seeking a more reliable method to predict the lifespan of welded structures.
Design/methodology/approach
Building on the fatigue test results of butt and cruciform joints, this research delves into the selection of fitting methods for the notch fatigue curve of welded joints. Both empirical formula and finite element methods (FEMs) were employed to assess the notch stress concentration factor at the toe and root of the two types of welded joints. Considering the mean stress correction and weld misalignment coefficients, the notch fatigue life curves were established using both direct and indirect methods.
Findings
An engineering example was employed to discern the differences between the direct and indirect approaches. The findings highlight the enhanced reliability of the indirect method for fitting the fatigue life curve.
Originality/value
While the notch stress approach is extensively adopted due to its accurate prediction of component fatigue life, most scholars have overlooked the importance of its curve fitting methods. Existing literature scantily addresses the establishment of these curves. This paper offers a focused examination of fatigue curve fitting techniques, delivering valuable perspectives on method selection.
Keywords
Acknowledgements
The paper is funded by the “National Natural Science Foundation of China” (No: 52271023) and “Scientific Research Project of Liaoning Provincial Department of Education” (No: LJKZ0493). The authors would like to express their gratitude to them for their support to this research.
Citation
Xue, S., He, Z., Chen, B. and Xu, J. (2024), "Research on fatigue curve fitting methods based on the notch stress approach", International Journal of Structural Integrity, Vol. 15 No. 2, pp. 246-261. https://doi.org/10.1108/IJSI-10-2023-0106
Publisher
:Emerald Publishing Limited
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