PSI - Issue 75

Francesco Collini et al. / Procedia Structural Integrity 75 (2025) 375–381 F. Collini et al. / Structural Integrity Procedia 00 (2025) 000–000

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6

Fig. 4. Multiaxial fatigue test results with di ff erent load shift angle compared with theoretical predictions through the ALM model limited to sharp V notches and describe by Eq 6.

experimental tests. Further fatigue tests are ongoing to strengthen the validation and to extend the approach to L-PBF Ti6Al4V specimens with di ff erent notch opening angles as well as varying load ratios.

5. Conclusions

In this paper, a preliminary validation of the Atzori–Lazzarin–Meneghetti approach, extended to multiaxial load ing conditions, applied to V-notched cylindrical additively manufactured Ti6Al4V specimens, was investigated. The approach estimates the fatigue thresholds expressed in terms of the remote threshold stress range as a function of an equivalent crack length and an equivalent threshold N-SIF, accounting for the material properties, loading modes, and geometry of the components by using the Averaged SED approach. In this paper, axial and torsional fatigue thresholds were evaluated through the staircase procedure to determine the structural control volume for modes I and III. Then, the ALM diagram was used to compare the theoretical predictions with the preliminary multiaxial fatigue test results, showing good correlation.

Acknowledgements

This study was carried out within the MICS (Made in Italy—Circular and Sustainable) Extended Partnership and re ceived funding from the European Union Next-GenerationEU (PIANO NAZIONALE DI RIPRESA E RESILIENZA (PNRR)—MISSIONE 4 COMPONENTE 2, INVESTIMENTO 1.3—D.D. 1551.11-10-2022, PE00000004).

References

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