PSI - Issue 42

Available online at www.sciencedirect.com Structural Integrity Procedia 00 (2019) 000 – 000 Available online at www.sciencedirect.com ^ĐŝĞŶĐĞ ŝƌĞĐƚ

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Procedia Structural Integrity 42 (2022) 390–397

© 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the 23 European Conference on Fracture – ECF23 Abstract In the present work, the hydrogen/material interaction with two austenitic steel types, created via a completely different alloying strategy, is investigated. The two steels include 304L austenitic stainless steel (ASS) and 18Mn-0.6C twinning-induced plasticity (TWIP) steel. Constant extension rate tensile tests are performed to evaluate the influence of hydrogen on the deformation and fracture mechanisms. A reference condition without hydrogen is compared to a seven days electrochemically hydrogen precharged condition. 304L ASS shows transformation to α’ - martensite without hydrogen, while hydrogen increases the α’ -martensite fraction and additionally enables the transf ormation to ε -martensite. The fracture surface has a transgranular, quasi-cleavage appearance. The TWIP steel shows deformation twinning without hydrogen, while abundant ε -martensite transformation is observed in the presence of hydrogen. The fracture type is intergranular due to the high cracking sensitivity of the grain boundaries. © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of 23 European Conference on Fracture - ECF23 Keywords: Austenitic steel; Hydrogen embrittlement; Martensitic transformation; Fractography; Electron backscatter diffraction 1. Introduction Designing strong and at the same time ductile materials has been one of the key challenges for metallurgists. Austenitic steel types show this extraordinary combination of properties due to the possibility of exploiting alternative deformation mechanisms apart from the well-known dislocation slip, i.e. stacking fault formation, deformation twinning and martensitic transformation. The latter two lead to an increased ductility by the twinning-induced is a 23 European Conference on Fracture - ECF23 Influence of hydrogen on deformation and fracture mechanisms in austenitic steel types Lisa Claeys*, Tom Depover, Kim Verbeken Ghent University, Department of Materials, Textiles and Chemical Engineering, Technologiepark 46, 9052 Zwijnaarde, Belgium

* Corresponding author. Tel.: +32 9 331 04 60 E-mail address: Lisa.Claeys@UGent.be

2452-3216 © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of 23 European Conference on Fracture - ECF23

2452-3216 © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the 23 European Conference on Fracture – ECF23 10.1016/j.prostr.2022.12.049