PSI - Issue 68

Tsanka Dikova et al. / Procedia Structural Integrity 68 (2025) 99–105 Tsanka Dikova & Natalina Panova / Structural Integrity Procedia 00 (2025) 000–000

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corrosion destruction in depth of the laser melted layers was selective by δ-ferrite destruction in the form of shallow (40-100 µm) equiaxed pits. It was revealed that the main mechanism of corrosion failure in wrought and laser melted steel was identical – selective destruction of the corrosion nonresistant δ-ferrite phase in the form of pits. The morphology and size of corrosion pits were different, which was determined by the δ-ferrite morphology in the microstructure. From the point of view of resistance to corrosion failure, laser surface melting of AISI 321 steel improves conditions for enhanced durability of the dental and implant constructions. Acknowledgements This study is financed by the European Union-NextGenerationEU, through the National Recovery and Resilience Plan of the Republic of Bulgaria, project № BG-RRP-2.004-0009-C02. References Alhajhamoud, M., Candan, L., Ilgaz, M. A., Cinar, I., Ozbey, S., Čorović, S., ... & Kayahan, E., 2022. 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