PSI - Issue 68

J. Köckritz et al. / Procedia Structural Integrity 68 (2025) 962–968 J. Köckritz et al. / Structural Integrity Procedia 00 (2025) 000–000

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4. Conclusions The fatigue life of topology and aerodynamically optimized PBF-LB/M Al2139 components was investigated with two different surface conditions, as built (AB) and trowalised (TW), under a realistic multiaxial load case. The surface has been characterized non-destructively by confocal microscopy and the crack-initiating defects were evaluated by fractography for their size, shape and position. The following conclusions can be drawn from the investigation: • TW significantly reduced R a , R z and S a but showed no effect on fatigue life of the components due to incomplete removal of valleys and defects. The effectiveness of TW is highly dependent on print quality. • For TW components, the crack-initiating defects were larger and further away from the maximal stress than for AB components, because TW removed small irregularities in highest stress area, which led to larger defects further away displaying the highest stress concentration • Crack location in the thin-walled component varied widely, dependent on defect position and size • Surface characterization should be conducted on large area in proximity to critical stresses, as printing errors can cause crack initiation at apparently non-critical areas. Optical methods are likely to underestimate the size of the defects. Acknowledgements This investigation is co-financed by tax funds on the basis of the budget approved by the Saxon state parliament. The project number is 100649753. We thank M. Härtel, who kindly provided the material data for Al2139-AM. 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