PSI - Issue 75

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia (2025) 000 – 000

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 75 (2025) 633–641

Fatigue Design 2025 (FatDes 2025) Hydrogen effect on self-heating response under cyclic loading of a martensitic steel KADIRI Mounir a , DEMMOUCHE Younès a , DHONDT Matthieu a , CAËR Célia a , VUCKO Flavien b , CALLOCH Sylvain a

a IRDL – UMR CNRS 6027 – ENSTA Bretagne, 2 Rue François Verny, Brest 29200, France a French Corrosion Institute – RISE, 220 Rue Pierre Rivoalon, Brest 29200, France

© 2025 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 the responsibility of Dr Fabien Lefebvre with at least 2 reviewers per paper The results obtained shows a significant difference in the self-heating curve between the base material and the hydrogen charged coated material, confirming a hydrogen effect on the volumetric energy dissipation. Moreover, the coating itself exhibits dissipative behavior due to its ductile nature and, as a consequence, influences the self-heating curve of the base material. © 2025 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 Fatigue Design 2025 organizers Abstract The increase in the use of High Strength Steels (HSS) in critical structural components has been a focal point of interest fo r offshore and subsea applications for several years, particularly in the manufacturing of mooring chains for floating wind turbines. However, these steels must be used with caution in a marine environment because they are susceptible to hydrogen embrittlement. When a critical hydrogen concentration is combined with cyclic mechanical loading, damage can occur and, in the worst cases, lead to failure at lifetimes shorter than expected. As fatigue is a probabilistic phenomenon that depends on many parameters, its testing campaigns are time consuming. To overcome this issue, the self -heating method offers a time saving alternative for studying the fatigue properties of various materials, espe cially metals. This method, which relies on temperature measurements during cyclic loading (Doudard 2004), (Munier 2012), was applied to a martensitic grade 12.9 steel in order to determine the effect of hydrogen on its fatigue behavior. The primary objective of this paper is to demonstrate the effect of hydrogen on the material’s self -heating curve, which shows the normalized volumetric energy dissipation as a function of the applied stress amplitude. To this end, self-heating tests were carried out on three specimens’ configurations: base material, hydrogen charged and coated material and uncharged coated material. Hydrogen charging was performed by cathodic polarization. The coating was applied by electrodeposition and was used to limit hydrogen desorption from the charged specimens as well as to determine its effect on the dissipation energy in uncharged coated specimens.

2452-3216 © 2025 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 Fatigue Design 2025 organizers

2452-3216 © 2025 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 the responsibility of Dr Fabien Lefebvre with at least 2 reviewers per paper 10.1016/j.prostr.2025.11.065