PSI - Issue 42

Iulian-Ionut AILINEI et al. / Procedia Structural Integrity 42 (2022) 1422–1427 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Using finite element analysis, the resonant frequencies and shape of the natural vibration modes for all specimens were found. The first normal mode of vibration was out of plane bending, the second mode was in-plane bending, and the second was out of plane bending – the second order was the third mode, respectively. In Fig. 7 are plotted the results for frequency response functions are planned from finite element analyses.

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Fig. 7. Frequency response functions from FEA, a) specimen cut at 0°, b) specimen cut at 45°, and c) specimen cut at 90°

The frequency response functions results for experimental investigation vs finite element analysis considering specimens cut at 0° are presented in Fig. 8. A good correlation between the results was observed.

Fig. 8. Frequency response functions Test results vs FEA

5. Conclusion In this study, the vibrational behaviour of S600Mc specimens from sheet metal at different orientations θ = 0°, 45°, and 90° to the rolling direction was explored. The vibration measurement showed that the anisotropy generated by the rolling movement considerably influences the damping ratio. Damping ratios identified after harmonic loading were inputted to numerical models; therefore were in perfect agreement with test results. The damping ratio has been proven to influence high cycle fatigue performance significantly; hence, to account for the anisotropy, different finite element models to incorporate various damping loss factors must be considered for accurate fatigue failure prediction. The numerical models are as helpful as their degree of correlation with physical experiments.