PSI - Issue 68

S.R. Raghuraman et al. / Procedia Structural Integrity 68 (2025) 769–775 S.R. Raghuraman et al. / Structural Integrity Procedia 00 (2025) 000–000

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Barkhausen noise measurement system. Micrographs taken by light-, confocal- and scanning electron microscopy illustrate the development of surface damage in terms of intrusions, extrusions and microcracks. The primarily loaded specimens were reconditioned by mechanical and electrical polishing to remove surface damage. The initial condition specimens and the primarily loaded specimens with and without reconditioning were subjected to secondary loading at 1 kHz up to the transition to the Very-High-Cycle-Fatigue regime until failure. The influence of the reconditioning process can be proven by the increase in the re-use potential by a factor of 12.41. Despite this positive effect of reconditioning, there was still a considerable difference compared to the lifetimes achieved by the initial condition specimens. In addition to mechanical and electrochemical surface treatment, further reconditioning measures (e.g. thermal reconditioning) are planned in the project, which are to be determined depending on the type and extent of the primary loading and the possible use in the context of secondary loading. The overall aim of the joint project is therefore to incorporate the information obtained into a model that enables the prediction of the re-use potential and the remaining fatigue life of steel components already in service. Acknowledgements The authors would like to thank the German Research Foundation (DFG) for funding the joint project (KR 1999/52 1, STA 1133/20-1). Furthermore, the authors of the WWHK would like to thank the University of Kaiserslautern for the financial support in the procurement of experimental infrastructure. Finally, thanks go to the companies Shimadzu Germany/Europe and EVIDENT Germany for their technical support. References Cooper, D. R., Skelton, A. C., Moynihan, M. C., & Allwood, J. M. (2014). Component level strategies for exploiting the lifespan of steel in products. Resources, Conservation and Recycling , 84 , 24–34. https://doi.org/10.1016/j.resconrec.2013.11.014 Haghshenas, A., & Khonsari, M. M. (2019). On the removal of extrusions and intrusions via repolishing to improve metal fatigue life. Theoretical and Applied Fracture Mechanics , 103 , 102248. https://doi.org/10.1016/j.tafmec.2019.102248 Polák, J., Lepistö, T., & Kettunen, P. (1985). Surface topography and crack initiation in emerging persistent slip bands in copper single crystals. Materials Science and Engineering , 74 (1), 85–91. https://doi.org/10.1016/0025-5416(85)90112-0 Radaj, D., & Vormwald, M. (2007). Ermüdungsfestigkeit: Grundlagen für Ingenieure (3., neubearb. und erw. Aufl.). Springer. https://doi.org/10.1007/978-3-540-71459-0 Raghuraman, S. R., Shrivastava, A, Weber, F., Krupp, U., & Starke, P. (Eds.) (2023). Bewertung von Volumen- und Oberflächenschäden bei HCF- und VHCF- Beanspruchung von Vergütungsstählen . Deutscher Verband für Materialforschung und –prüfung e.V. Sagar, S., Parida, N., Das, S., Dobmann, G., & Bhattacharya, D. (2005). Magnetic Barkhausen emission to evaluate fatigue damage in a low carbon structural steel. International Journal of Fatigue , 27 (3), 317–322. https://doi.org/10.1016/j.ijfatigue.2004.06.015 Schneider, E., Bindseil, P., Boller, C., & Kurz, W. (2012). Stand der Entwicklungen zur zerstörungsfreien Bestimmung der Längsspannung in Bewehrungsstäben von Betonbauwerken. Beton- Und Stahlbetonbau , 107 (4), 244–254. https://doi.org/10.1002/best.201100083 Shrivastava, A., Raghuraman, S. R., Weber, F., Gulbay, O., Gramlich, A., Starke, P., & Krupp, U. (unpublished, invited manuscript in preparation (2025)). Increasing the re-use potential of high strength steels by an increased fatigue resistance through surface treatments. Steel Research International . Starke, P. (2019). StressLife tc – NDT-related assessment of the fatigue life of metallic materials. Materials Testing , 61 (4), 297–303. https://doi.org/10.3139/120.111319