## 4 Conclusions  
This study compares the corrosion resistance of LPBF-generated 316L samples with wrought sheet 316L samples. The evolution of the corrosion mechanism over time is defined in this paper, being considered for the first time. This contribution is fundamental to understanding the impact of time on the corrosion resistance of the LPFB and wrought 316L SS. Based on the findings of the current paper, the following conclusions can be delivered:  
LPBF samples show a larger grain size than wrought sheet 316L stainless steel. The metallic alloy elements have a homogeneous distribution, while the carbon and silicon are localised in the molten front and voids. Despite these imperfections, the LPBF 316L samples are found to have a high kinetic and thermodynamic corrosion resistance. The large size of the grain increases the corrosion resistance of the LPBF samples due to the mitigation of the grain boundary cathodic effect. As a result, the LPBF 316L SS presents better corrosion resistance than wrought 316L SS, contrary to some results found in the literature [6]. According to a study in the literature, an LPBF sample passive film current density was 135 \(\mu\)A/cm\({}^{2}\)[6]. In contrast, the passive film current density was 0.953 \(\mu\)A/cm\({}^{2}\) in this study. The breaking passive film potential was cited as 0 V vs. Ag/AgCl 3 M KCl [6] in the literature, whereas in this study, this potential was 1 V. Note that the difference in these values is attributed to the varying aggressive environment used in these studies: 0.1 M HCl [6] for the literature and 0.6 M NaCl for this study. Both samples show similar types of corrosion (mixed) and controls of the anodic and cathodic branch.  
The evolution of the corrosion mechanisms over time in saltwater is similar for both types of 316L SS with the presence of the passive film. The corrosion mechanism is stable over time. The corrosion resistance increased with time for the LPBF samples, while the wrought sheet 316L stainless steel decreased for immersion times equal or shorter than 96 h.  
Laser powder bed fusion manufacturing technology allows for the design of structures with complex shapes and high corrosion resistance that can be employed in several applications. This technology is used in the industrial field, as demonstrated by the origin of the LPBF samples, which were supplied by Croft Additive Manufacturing Ltd., a division of Croft Filters, Warrington, UK.  
Conceptualization, J.I.A.-T., A.B., M.C.S., T.T.O., S.P.M., P.L.F., R.I.D. and S.T.-W.; methodology, J.I.A.-T.; validation, J.I.A.-T.; formal analysis, J.I.A.-T.; investigation, J.I.A.-T.; resources, A.B.; data curation, J.I.A.-T.; writing--original draft preparation, J.I.A.-T.; writing--review and editing, J.I.A.-T., A.B., M.C.S., T.T.O., S.P.M., T.L.F., R.I.D. and S.T.-W. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Figure 8: EDS mapping of the corroded wrought (**a**) and LPBF (**b**) samples.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** The datasets generated during and/or analysed during the current study are available in the manuscript.  
**Acknowledgments:** Croft Additive Manufacturing Ltd. supported this paper by supplying the LPBF sample.  
**Conflicts of Interest:** The authors declare no conflict of interest.