PSI - Issue 57

Grégoire Brot et al. / Procedia Structural Integrity 57 (2024) 53–60 G. Brot et al. / Structural Integrity Procedia 00 (2023) 000–000

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5. Conclusions

In this study, SH testing was performed on several grades of Ti-6Al-4V-LPBF di ff ering by their microstructure or their porosity level. This was done to assess the sensitivity to microstructure and to porosity of this fast fatigue characterization method. The main conclusions of this work are: • Thermal dissipation is very limited before failure. Therefore, transition from first to second SH regime is not clearly visible for Ti-6Al-4V-LPBF and SH curves do not discriminate materials with di ff erent microstructures of porosity levels. • First self-heating regime is slightly more intense when tested at higher load frequencies due to anelastic thermal sources. • A tensile prestrain before SH testing reduces the threshold stress amplitude between SH regimes and strongly enhance thermal dissipation in the second regime.

Acknowledgements

This work was supported by ONERA and CETIM through their contribution in Additive Factory Hub (AFH), a French research consortium working on metallic additive manufacturing.

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