PSI - Issue 42

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Author name / Structural Integrity Procedia 00 (2019) 000–000

J.R. Antunes et al. / Procedia Structural Integrity 42 (2022) 588–593

593

 Microstructure of the weld. FSW produces softened heat-affected zones. Due to the heat input being higher on the advancing side of the weld, this will typically be the preferred initiation location when the remaining effects are not dominant, in case there are no pre-existing defects in the sample.  Residual stresses. FSW creates regions of tensile residual stresses within the weld region, which will help to propagate any pre-existing defects. After laser peening, the residual stresses from the surface treatment will superimpose over the ones from FSW. In this study, a peak compressive stress of 180 MPa was achieved in the loading direction, which improved the fatigue life of as-welded samples up to a factor of 2.4, recovering 65% of the life compared to the pristine aluminium material. References Smyth, N. A., Toparli, M. B., Fitzpatrick, M. E., & Irving, P. E. (2019). Recovery of fatigue life using laser peening on 2024-T351 aluminium sheet containing scratch damage: The role of residual stress. Fatigue and Fracture of Engineering Materials and Structures, 42(5), 1161–1174 Domenico Furfari , Nikolaus Ohrloff, Elke Hombergsmeier, Ulrike Heckenberger, Vitus Hol-zinger, Laser Shock Peening as Surface Technology to Extend Fatigue Life in Metallic Airframe Structures, in the 29th ICAF symposium, 7-9 June 2017, Nagoya, Japan