PSI - Issue 13

Mehul Lukhi et al. / Procedia Structural Integrity 13 (2018) 607–612 M. Lukhi et al. / Structural Integrity Procedia 00 (2018) 000–000

611 5

Fig. 7: E ff ect of strength on fatigue life

Fig. 8: E ff ect of temperature on fatigue life

life. The e ff ect of temperature on fatigue life is studied by employing values of Young’s modulus, hardening exponent and initial yield stress of material for the respective temperatures from Šamec et al. (2011), respectively. The e ff ect of temperature on the predicted lifetime for a strain amplitude ∆ = 10% is shown in Fig. 8. It can be seen that the lifetime increases with temperature. This prediction complies qualitatively with the experiments of Petrenec et al. (2010).

4. Summary

In the present study, a micromechanical unit cell model is employed to simulate the lifetime of nodular cast iron under cyclic loading in the LCF regime. This model only uses geometrical features of NCI microstructure and material parameters defining matrix behavior to understand fatigue behavior qualitatively and quantitatively. The e ff ects of graphite shape, load sequence, strength of di ff erent grades of NCI and of temperature were studied.

Acknowledgements

The authors are grateful towards ESF (European social fund) for providing financial assistance under state innova tion project (SAB application number: 100284311). The authors are grateful to Peter Hübner for fruitful discussions as well as to Thomas Mottischka for providing experimental data.

References

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