PSI - Issue 39

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

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 39 (2022) 515–527

© 2021 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 CP 2021 – Guest Editors Abstract Possessing the highest combination of strength and toughness ever-recorded among bainitic steels, nanostructured bainite is a significant advanced steel due to its simplicity with regards to the alloy design and processing. The outstanding monotonic properties do not necessarily correlate with an optimum fatigue performance. Therefore, prior to the industrial implementation of the microstructure, intensive laboratory-scale research should be carried out to clearly rationalize the microstructure’s behavior under cyclic loadings. This work aims at investigating the first stages of the fatigue crack propagation in a nanobainitic steel. For this purpose, interrupted fatigue testing, with crack initiation assisted by the presence a of focused ion beam (FIB) defect, was conducted, ensuring that the short-crack regime applies, and the crack path was morphologically examined. © 2021 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 CP 2021 – Guest Editors Keywords: Nanostructured Bainitic Steels; Short Cracks; Fatigue Testing; Crack Path 1. Introduction Nanostructured bainitic steels are promising steel grades that have been the centre of many studies due to the lean chemical compositions and typical isothermal treatments at relatively low temperatures, without the need for expensive manufacturing routes [Caballero, et al.(2002, Caballero, et al.(2007, Garcia-Mateo, et al.(2015, Morales Rivas, et al.(2016, Müller, et al.(2017, Mueller, et al.(2016, Caballero and Bhadeshia(2004)]. To date, the microstructure possesses the highest combination of the strength and toughness (2.2 GPa-30 MPa·m 1/2 ) among all 0 microstructu 7th International Conference on Crack Paths Fatigue behavior of nanostructured bainite: A morphological study of crack path Lucia Morales-Rivas*, Ava Azadi, Eberhard Kerscher Technische Universität Kaiserslautern (TUK), Materials Testing, Gottlieb-Daimler-Str., Kaiserslautern D-67663, Germany

* Corresponding author. E-mail address: rivas@mv.uni-kl.de

2452-3216 © 2021 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 CP 2021 – Guest Editors

2452-3216 © 2021 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 CP 2021 – Guest Editors 10.1016/j.prostr.2022.03.125