PSI - Issue 54

Daria Pałgan et al. / Procedia Structural Integrity 54 (2024) 322 –331

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Daria Pałgan et al./ Structural Integrity Procedia 00 (2023) 000 – 000

It should be noted that although similar contents were measured in all studied steels using both charging methods the hydrogen preferentially occupied reversible trapping sites when cathodically charged and irreversible trapping sites when gaseous charging was used. From this point of view, it is of exceptional importance to investigate how the mechanical properties are affected by these charging methods that results in similar total hydrogen content, but with different trapping sites of hydrogen.

Figure 8. Effect of temperature on the hydrogen uptake for a) A516, b) 304L and c) 316L steels. Note that the scale of the y-axis is different between the diagrams. 4. Conclusions One low alloyed carbon steel (A516 Grade 70) and two austenitic stainless steels (304L UNS S30403 and 316L UNS S31603) were charged with hydrogen using cathodic and gaseous charging methods utilizing different charging parameters. The hydrogen uptake in steel samples were measured and compared. The conclusions from this study are as follows: • Cathodic charging results in hydrogen preferentially occupying reversible trapping sites in the studied steels, while gaseous charging results in more pronounced hydrogen uptake in irreversible trapping sites. • Optimization of charging parameters for both cathodic and gaseous charging methods have a significant impact on the hydrogen uptake as well as where hydrogen is trapped in the investigated steels. • Increasing the temperature results in more pronounced hydrogen uptake than increasing the charging time for both for both charging methods. Acknowledgments The authors greatly acknowledge the support from members of the Corrosion Forum Consortium at Swerim AB, Namurata Pålsson and Emil Cederberg from Alleima, Johan Pilhagen from Outokumpu, Caroline Klar Jaans, Esa Virolainen and Ulf Bexell from SSAB. References Ajito, S., Hojo, T., Koyama, M., & Akiyama, E. (2022). Effects of Ammonium Thiocyanate and pH of Aqueous Solutions on Hydrogen Absorption into Iron under Cathodic Polarization. Tetsu-to-Hagane, 108(11), TETSU-2022-043. https://doi.org/10.2355/tetsutohagane.TETSU-2022-043 Bai, S., Liu, L., Liu, C., & Xie, C. (2023). Phase-Field Insights into Hydrogen Trapping by Secondary Phases in Alloys. Materials, 16(8), 3189. https://doi.org/10.3390/ma16083189 Barrera, O., Bombac, D., Chen, Y., Daff, T. D., Galindo-Nava, E., Gong, P., Haley, D., Horton, R., Katzarov, I., Kermode, J. R., Liverani, C., Stopher, M., & Sweeney, F. (2018). Understanding and mitigating hydrogen embrittlement of steels: a review of experimental, modelling and design progress from atomistic to continuum. Journal of Materials Science, 53(9), 6251 – 6290. https://doi.org/10.1007/s10853-017-1978-5 Brass, A.-M., & Chêne, J. (2006). Hydrogen uptake in 316L stainless steel: Consequences on the tensile properties. Corrosion Science, 48(10), 3222 – 3242. https://doi.org/10.1016/j.corsci.2005.11.004 Djukic, M. B., Bakic, G. M., Sijacki Zeravcic, V., Sedmak, A., & Rajicic, B. (2019). The synergistic action and interplay of hydrogen embrittlement mechanisms in steels and iron: Localized plasticity and decohesion. Engineering Fracture Mechanics, 216, 106528. https://doi.org/10.1016/j.engfracmech.2019.106528 Djukic, M. B., Bakic, G. M., Zeravcic, V. S., Sedmak, A., & Rajicic, B. (2016). Hydrogen Embrittlement of Industrial Components: Prediction, Prevention, and Models. Corrosion, 72(7), 943 – 961. https://doi.org/10.5006/1958