PSI - Issue 68

M. Mahatab et al. / Procedia Structural Integrity 68 (2025) 815–821 M. Mahatab and R. Ranjan / Structural Integrity Procedia 00 (2025) 000–000

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fracture mechanics (SBFM) model to analyze the impact of the HFMI treatment under constant and variable amplitude loading conditions based on the input data from the existing literature. The study's findings indicate that the SBFM model effectively predicts the fatigue life of as-welded cruciform joints, with good agreement between predicted and existing experimental results. The model predictions showed that HFMI treatment substantially improves the fatigue life of welded joints for all three loading conditions. The reduction in fatigue life under variable amplitude loading conditions demonstrates the ability of the SBFM model to predict the loading effects on the fatigue life of welded joints. The Crack-shape evolution curves showed the semi-elliptical crack turned into a through-width crack at lower stress levels for as-welded joints and the higher final crack aspect ratio at the verge of failure for higher stress levels. In the future, efforts will be made to validate the SBFM crack growth analysis for as welded and HFMI-treated conditions under CA and VA loading by measuring crack shape evolution during fatigue testing. After validation, the SBFM model will be used as a tool to develop the reliability-based fatigue design guidelines for as-welded and HFMI-treated welded joints. Acknowledgements Support for this work provided by the Ministry of Education, Government of India, under the PMRF scheme, is gratefully acknowledged. References Banno, Y., Kinoshita, K. and Barsoum, Z. 2024. “Life extension analysis considering crack opening-closing behavior in HFMI-treated welds,” Welding in the world, 68(2), pp. 333–345. Campagnolo, A., Belluzzo, F., Yıldırım, H.C. and Meneghetti, G., 2022. Fatigue strength assessment of as-welded and HFMI treated welded joints according to structural and local approaches. International Journal of Fatigue, 155, p.106584. 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