PSI - Issue 74

Jaromír Brůža et al. / Procedia Structural Integrity 74 (2025) 1–8

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Jaromír Brůža / Structural Integrity Procedia 00 (2025 ) 000–000

refinement documented in Fig. 4. The high occurrence of TBs documented for SLM and Praxair steel (see Fig. 3e,f) may be related to the presence of the massive solid-state transformation, as it is known to be accompanied by twinning (see e.g. ( Brooks et al., 1991 )). Other TEM studies related to the specific solidification sequence, as well as the assessment of dislocation density and their impact on tensile performance of grain-refined L-PBF 316L steels, are in progress. In summary, the present work highlights the vital role of the chemical composition of 316L stainless steel powder on the solidification behavior of the material during its L-PBF consolidation. Even minor variations in steel chemistry, still within the bounds of the standard, may lead to substantially diverse microstructural states of L-PBF 316L stainless steels manufactured under identical processing conditions. Characteristic microstructural features ( size and shape of grains, and fraction of LAGBs and TBs) resulting from two distinctly different solidification paths were documented, and their impact on the hardness of L-PBF 316L stainless steels was pointed out. Acknowledgement The authors would like to express their gratitude for the financial support of the Czech Science Foundation within the project No. 23-05372S. Th e support of this research by the Czech Academy of Scienc es in Strategy AV21: Research programme “ Breakthrough Technologies for the Future – Sensing, Digitisation, Artificial Intelligence and Quantum Technologies” is gratefully acknowledged. References Brooks, J.A., Baskes, M.I. , Greulich, F.A., 1991. Solidification modeling and solid-state transformations in high-energy density stainless steel welds. Metall Trans A 22, 915–926. https://doi.org/10.1007/BF02659001 Dryepondt, S., Nandwana, P. , Fernandez -Zelaia, P., List, F., 2021. 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