PSI - Issue 4

J. Maierhofer et al. / Procedia Structural Integrity 4 (2017) 19–26

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J. Maierhofer/ Structural Integrity Procedia 00 (2017) 000–000

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empirical model described by Eqs. (6) and (7) gives qualitatively correct results; however, more work to improve the model quality is currently underway.

4. Conclusion

The lifetime of cyclically loaded components can be significantly higher than estimated by conventional computational models based on laboratory specimen tests. The main reasons are (i) residual compressive stresses introduced due to manufacturing processes, (ii) overloads and (iii) small loads, as they occur during typical service load spectra. In this paper it was shown that those effects may have a big influence on the fatigue crack propagation rate and therefore on the residual lifetime of a component. Simple analytical models were suggested for considering these effects in computational crack growth predictions. If these effects are neglected, the model predictions are conservative.

Acknowledgements

Financial support by the Austrian Federal Government (in particular from Bundesministerium für Verkehr, Innovation und Technologie and Bundesministerium für Wissenschaft, Forschung und Wirtschaft) represented by Österreichische Forschungsförderungsgesellschaft mbH and the Styrian and the Tyrolean Provincial Government, represented by Steirische Wirtschaftsförderungsgesellschaft mbH and Standortagentur Tirol, within the framework of the COMET Funding Programme is gratefully acknowledged.

References

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