PSI - Issue 51

Kamila Kozáková et al. / Procedia Structural Integrity 51 (2023) 145–151 K. Kozáková et al. / Structural Integrity Procedia 00 (2022) 000–000

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Fig. 10. Fracture surface, combination of transranular and intergranular crack propagation.

4. Conclusion Risk volume has a strong effect on the fatigue lifetime of specimens, especially on the fatigue limit. Specimens with a larger risk volume have a shorter fatigue lifetime than specimens with a smaller risk volume. In material 1.4306, a change in the failure mechanism was observed at higher numbers of cycles. The influence of risk volume was greater in the case of 1.4306 stainless steel than in 1.4307. Acknowledgements The research was supported by the Czech Science Foundation, project No. 21-14886S. References Furuya, Y., 2010. Size effects in gigacycle fatigue of high-strength steel under ultrasonic fatigue testing. Procedia Engineering 2, 485–490. Furuya, Y., 2008. Specimen size effects on gigacycle fatigue properties of high-strength steel under ultrasonic fatigue testing. Scripta Materialia 58, 1014–1017. Klusák, J., Horník, V., Lesiuk, G., Seitl, S., 2021. Comparison of high- and low-frequency fatigue properties of structural steels S355J0 and S355J2. Fatigue and Fracture of Engineering Materials and Structures 44, 3202–3213. Klusák, J., Kozáková, K., Fintová, S., Seitl, S., 2022. Fatigue lifetimes of 1.4306 and 1.4307 stainless steels subjected to ultrasonic loading. Procedia Struct. Integr., 23 European Conference on Fracture 42, 1369–1375. Paolino, D.S., Tridello, A., Chiandussi, G., Rossetto, M., 2014. On specimen design for size effect evaluation in ultrasonic gigacycle fatigue testing. Fatigue and Fracture of Engineering Materials and Structures 37, 570–579. Tridello, A., Niutta, C.B., Berto, F., Paolino, D.S., 2021. Size-effect in Very High Cycle Fatigue: A review. International Journal of Fatigue 153, 106462. Furuya, Y., 2011. Notable size effects on very high cycle fatigue properties of high-strength steel. Materials Science and Engineering A 528, 5234– 5240.