PSI - Issue 75

J. Havia et al. / Procedia Structural Integrity 75 (2025) 43–52 Havia et al. / Structural Integrity Procedia (2025)

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4. Conclusions The current study experimentally evaluated the fatigue strength of aluminum DED components joined with plate structure applying different techniques (DED on plate, DED component welded on plate, and DED on DED cladded surface). In addition, numerical analyses were carried out to obtain fatigue notch factors for the fatigue assessment using the notch stress concepts. Fatigue design recommendations for nominal stress and effective notch stress methods were found valid for additive manufacturing on the load carrying plate. Furthermore, the multiparametric 4R method considering residual stresses and local cyclic behavior was found to result in the most accurate fatigue strength assessment. Reinforcement or stress relief via geometric shapes could be designed and implemented with DED technique. The following conclusions can be drawn: • Adding features with DED-Arc for load carrying aluminum structures could be recommended • Deposition of detail directly on the result was the best fatigue performance as residual stresses were lower than after welding feature on the plate • 4R method considering local stress range was beneficial for evaluating effect of residual stresses Acknowledgements The work was carried out in the AluWeld project (Grant ID: 6232/31/2022) financially supported by Business Finland. The work of Mr. Tomi Suikkari is appreciated regarding the specimen manufacturing. Baumgartner, J., & Bruder, T. (2013). An efficient meshing approach for the calculation of notch stresses. Welding in the World , 57 (1), 137 – 145. https://doi.org/10.1007/s40194-012-0005-3 Bruzzo, F., Alberghini, M., Bertinetti, A., Tommasi, A., Riede, M., Pullini, D., & López, E. (2024). Characterization and simulation of AlSi10Mg reinforcement structures by direct energy deposition by means of laser beam and powder. Journal of Laser Applications , 36 (4). https://doi.org/10.2351/7.0001416 Fu, R., Han, X., Jing, C., Mao, H., Guo, Y., Tang, L., Liu, C., & Lei, H. (2024). Heat input adjustment process for unsupported aluminum alloy lattice struts continuous forming by wire arc-directed energy deposition. Journal of Materials Processing Technology , 332 . https://doi.org/10.1016/j.jmatprotec.2024.118550 Havia, J., Ahola, A., Kozlova, M., Baumgartner, J., & Björk, T. (2025). Fatigue strength assessment of arc-welded aluminum joints by local approaches. International Journal of Fatigue , 193 . https://doi.org/10.1016/j.ijfatigue.2024.108803 Hobbacher, A. F., & Baumgartner, J. (2024). IIW Collection Recommendations for Fatigue Design of Welded Joints and Components Third Edition . Lipiäinen, K., Ahola, A., Lund, H., Penttilä, S., Razavi, N., Skriko, T., Hensel, J., Moshtaghi, M., & Björk, T. (2025). Fatigue strength assessment of additively manufactured component considering local quality. Welding in the World . https://doi.org/10.1007/s40194-025 02002-9 Morgenstern, C. (2006). Kerbgrundkonzepte für die schwingfeste Auslegung von Aluminiumschweißverbindungen am Beispiel der naturharten Legierung AlMg4,5Mn (AW-5083) und der warmausgehärteten Legierung AlMgSi1 T6 (AW-6082 T6) . Technische Universität Darmstadt. Niemi, E., Fricke, W., & Maddox, S. J. (2018). Structural Hot-Spot Stress Approach to Fatigue Analysis of Welded Components . Springer Singapore. https://doi.org/10.1007/978-981-10-5568-3 Qin, F., Li, Y., Li, Y., Zhao, X., Chen, J., & Wang, X. (2025). Wire-arc directed energy deposition 7075-Sc aluminum alloy: Heat input adjustment forming quality, microstructure and mechanical properties. Journal of Alloys and Compounds , 1014 . https://doi.org/10.1016/j.jallcom.2025.178791 Scharf-Wildenhain, R., Haelsig, A., Hensel, J., Wandtke, K., Schroepfer, D., & Kannengiesser, T. (2023). Heat control and design-related effects on the properties and welding stresses in WAAM components of high-strength structural steels. Welding in the World , 67 (4), 955 – 965. https://doi.org/10.1007/s40194-022-01450-x Zapata, A., Bernauer, C., Celba, M., & Zaeh, M. F. (2024). Studies on the Use of Laser Directed Energy Deposition for the Additive Manufacturing of Lightweight Parts. Lasers in Manufacturing and Materials Processing , 11 (1), 109 – 124. https://doi.org/10.1007/s40516 023-00233-6 References