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This study presents the results of fatigue investigations performed on additively manufactured austenitic stainless steel 316L produced using the Laser Powder Bed Fusion (LPBF) technique. Fatigue tests were conducted under axial tension-compression loading for three different stress ratios: R = −1, −0.5, and 0. The primary objective of the research was to evaluate the influence of the stress ratio on fatigue life and to assess the applicability of the Smith-Watson-Topper (SWT) parameter and linear model for Sa-Sm diagram with the use of sensitivity on mean stress factor in describing the fatigue behavior of LPBF-manufactured material. Based on the experimental results, S-N fatigue curves were constructed for each loading condition, and corresponding analytical equations were determined to describe the relationship between stress amplitude and the number of cycles to failure. From these equations, load levels were calculated for three selected fatigue life ranges and subsequently correlated with the SWT parameter, enabling a comparative analysis of the combined effects of maximum stress and strain amplitude on fatigue damage evolution. In addition to mechanical testing, fracture surface analyses were carried out using scanning electron microscopy (SEM). The fractographic examination focused on identifying crack initiation sites and dominant fatigue damage mechanisms. The findings provide valuable insight into the fatigue performance of additively manufactured 316L stainless steel under different mean stress conditions and contribute to a better understanding of fatigue assessment methods for metallic materials produced by additive manufacturing technologies.
Keywords: Additive manufacturing, Laser Powder Bed Fusion (LPBF), Austenitic stainless steel 316L, Fatigue behavior, Mean stress effect,© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.