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) 219–233

© 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 purpose of this paper is to provide in a single document a comprehensive collection of the most relevant fatigue crack growth laws and models allowing a more effective review and comparison of the available tools and facilitating decision making. © 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: Fatigue crack growth; Crack Retardation Models; Looping Algorithms Fatigue Design 2025 (FatDes 2025) A comprehensive review of Fatigue Crack Growth laws and models Andrew Halfpenny a , Cristian Bagni a, *, Amaury Chabod b , Stephan Vervoort c a Hottinger Bruel & Kjaer UK Ltd, Advanced Manufacturing Park Technology Centre, Brunel Way, Rotherham, S60 5WG, United Kingdom b Hottinger Bruel & Kjaer France SAS, 2-4 rue Benjamin Franklin, 94370 Sucy-en-brie, France c Hottinger Bruel & Kjaer GmbH, Im Tiefen See 45, 64293 Darmstadt, Germany Abstract Fatigue is the most common cause of failure in structures subject to cyclic loading. Fatigue failure is a two-stage phenomenon consisting of a crack initiation stage followed by a propagation stage. Cracks can initiate due to fatigue but also as a result of manufacturing processes and material features such as inclusions or voids. Once a crack is present, if it is subject to a sufficiently high cyclic stress, it will propagate until failure. However, in some instances a crack can propagate into a low-stressed region causing the crack to stall and never propagate to failure. In this case the crack may be acceptable in-service as it might not compromise the durability of the component (damage tolerant approach). Fatigue crack growth refers to the propagation (or non-propagation) of cracks in structures subject to cyclic loading. Fatigue crack growth and damage tolerant analyses use fracture mechanics principles and therefore, the knowledge of pre-existing cracks is necessary. These pre-existing cracks can be detected in components using non-destructive techniques or assumed. From the second half of the 20th century, significant research effort was put in understanding and describing how cracks propagate under cyclic loading, including how to characterise the threshold, propagation and fast fracture regions, both from an experimental and numerical point of view, as well as how to account for mean stress effect and crack retardation. Unfortunately, this research effort is scattered in a multitude of scientific publications.

* Corresponding author. Tel.: +44-7768-091-654. E-mail address: cristian.bagni@hbkworld.com

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.2025.11.024