Abstract
The application of materials produced via additive manufacturing (AM) has been growing, with increasing interest in their interaction with hydrogen and how it may affect their properties. In this study, hydrogen absorption in stainless steels produced through additive manufacturing processes is analyzed. Depending on the application, stainless steels require cathodic protection for marine applications, also they are often connected to other components subjected to this process. Thus, understanding hydrogen absorption in these materials is crucial, especially since traditional techniques, such as Devanathan-Stachurski, may face challenges due to low diffusion coefficients in some steels. This research investigates the hydrogen absorption behavior of 316L and 2205 stainless steels, both produced via AM, and are compared with their wrought counterparts. Additionally, the influence of surface preparation on hydrogen absorption is also analyzed. For this, the Hydrogen Oxidation Current Method (HOCM) is employed, where materials are subjected to cathodic protection of -1148 mV vs. Ag|AgCl for varying durations (0.2, 2, 10, 20 and 72 hours). Following this, the samples undergo anodic polarization of +257 mV vs. Ag|AgCl to promote the oxidation of diffusible hydrogen absorbed by the material. The response current is directly related to the amount of hydrogen absorbed. When comparing the same surface preparation between AM and conventionally manufactured materials, no significant differences were observed in hydrogen absorption. However, for 316L-AM, the machined surface exhibited higher hydrogen absorption. Also, the surface/subsurface reaches a hydrogen saturation after 20 h of charging in all cases. Ongoing mechanical tests will also analyze the different conditions. This study highlights the importance of surface preparation and manufacturing methods on hydrogen interaction, contributing to a better understanding of the hydrogen embrittlement resistance of AM stainless steels. The HOCM experiments were simulated by using finite elements analyses (FEA) based on the Fick’s law of diffusion.