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) 642–649

© 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 In the tests it could be shown, that the specimens tested in water fail at a lower number of cycles than those in air. Also, a higher strain amplitude leads to higher stresses and to a shorter lifetime. Stresses in ER 308L are lower than those in AISI 321. Moreover, there is a low scatter in the tests, especially when compared with the literature. © 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 Keywords: AISI 321; ER 308L; EAF; HTW Fatigue Design 2025 (FatDes 2025) Fatigue tests of austenitic stainless steel AISI 321 and the weld metal ER 308L in air and high temperature water environment Nina Grözinger a, *, Georg Veile a , Martin Herzig a , Stefan Weihe a a MPA Stuttgart (Material Testing Institute University of Stuttgart), Pfaffenwaldring 32, 70569 Stuttgart, Germany Abstract Components under water conditions typically suffer more damage than such in an air environment. To estimate the difference quantitatively, strain-controlled fatigue tests in water and in air are carried out with strain amplitudes of 0.3 %, 0.4 %, 0.5 %. The temperature is in both 280 °C, the pressure in the water is 80 bar. The materials investigated are AISI 321 (1.4541) and ER 308L (1.4316) (weld material). In order to keep the strain amplitude in water and in air identical, the global displacement in air is measured with a linear variable differential transformer (LVDT). Out of this recorded LVDT signal, an analytical function for approximation of local strain is formed and then used for control in the associated fatigue test in high temperature water (HTW). a

* Corresponding author. Tel.: +49 711 6856251 E-mail address: nina.groezinger@mpa.uni-stuttgart.de

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.2025.11.066