PSI - Issue 25

R. Baptista / Procedia Structural Integrity 25 (2020) 186–194

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Author name / Structural Integrity Procedia 00 (2019) 000–000

4. Conclusions In this paper the author showed another application of the previously developed automatic FCG algorithm. Now applied to non-proportional out-of-phase loading conditions, it was possible to understand that FCG life is inversely proportional to the load phase angle. Comparing crack propagation under MTS criterion with the resulting T-Stress, one can conclude that negative T-Stress leads to crack direction stabilization, while under positive T-Stress crack trajectory tend to be unstable and crack kinking may occur. When compared with the biaxiality ratio B , FCG life was proportional to B , in the majority of simulated loading conditions. As several authors consider B an important factor to determine crack propagation direction, a new crack propagation model must now be defined, taking this parameter into account. Experimental verification will follow, especially considering non-proportional out-of-phase conditions.

Acknowledgements This work was supported by FCT, through IDMEC, under LAETA, project UID/EMS/50022/2019.

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