PSI - Issue 68

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Jan Klusák et al. / Procedia Structural Integrity 68 (2025) 660–665 Jan Klusák, Kamila Kozáková / Structural Integrity Procedia 00 (2025) 000–000

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Fig. 4. The method of fatigue life prediction of different notch The calculation of the values ( ) is repeated for the whole range of . 4. Conclusion

This paper introduces the use of strain energy density (SED) in the theory of critical distances. The critical distance is determined based on knowledge of SED and based on fatigue life curves obtained for smooth specimens and specimens with model notch. The critical distances are modified by the ratio of stress concentration factors of model (calibration) notch and the predicted notch. The critical distance suitable for predictions is thus determined and it can be used for fatigue life predictions of different notched specimens or components. Unlike classical critical distance theory, which uses and evaluates the average stress, the SED approach includes other stress components, so it would better describe the multiaxiality of stress in cases of complex loading. Acknowledgements This paper was created as part of the project No. CZ.02.01.01/00/22_008/0004631 Materials and technologies for sustainable development within the Jan Amos Komensky Operational Program financed by the European Union and from the state budget of the Czech Republic. The work was also supported by the Brno University of Technology through the project FSI-S-23–8240. Data availability The data used in this study is available at: https://10.5281/zenodo.14016775

References

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