PSI - Issue 53

Costanzo Bellini et al. / Procedia Structural Integrity 53 (2024) 227–235 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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manufacturing processes. The model considered for the approach comprised beam and shell elements since they are the base of streamlined FE models with less computing expense. The mismatch between the experimental and numerical load-displacement curve did not depend only on the geometrical unconformities, that is, the diameter of the produced trusses and the thickness of the skins were thinner than expected, but also on the values of mechanical properties adopted in the model. Therefore, the yield strength of the material was determined through the hardness test, and a difference between the value measured on a bulk specimen and that evaluated for a thin specimen was found. Probably, the different dimensions of the specimens led to a different thermal path in the specimens themselves, and, consequently, affected the yield strength of the material. Moreover, it must be remembered that the "net" theme of the printing machine was used to produce the lattice core, while the "melt" theme was employed for the bulk specimen. Therefore, also the process parameters may have an influence on the yield strength of the additively manufactured titanium alloy. The redetermined value of the yield strength was then employed in the numerical model, and the gap in the point of deviation from linearity in the load-displacement curve was reduced. Acknowledgements This research was supported by POR FESR Lazio 2014-2020, Strategic Projects-AoS Aerospace [AMHybridStructures project, 28143, rif. G06734/2020]. References Ashby, M., 2011. Hybrid Materials to Expand the Boundaries of Material-Property Space. Journal of the American Ceramic Society 94, 3 – 14. Ashby, M., 2013. Designing Architectured Materials. Scripta Materialia 68, 4 – 7. Bellini, C., Borrelli, R., Di Cocco, V., Franchitti, S., Iacoviello, F., Mocanu, L. P., Sorrentino, L., 2021. 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