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) 602–608

© 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 Abstract This study investigates the fatigue strength of arc-welded joints made of aluminium alloys and subjected to multiaxial variable amplitude loadings through the application of the Peak Stress Method (PSM). The PSM is an engineering approach that exploits the Strain Energy Density criterion to efficiently estimate the fatigue resistance of welded joints by using FE analyses with relatively coarse mesh. In its more recent formulation, the PSM has been extended to variable amplitude (VA) loading conditions through the integration of the linear damage rule. This study further advances the method by exploring, for the first time, its application to aluminium welded joints subjected to multiaxial VA loading. Specifically, the proposed approach is successfully validated against experimental data taken from the literature and relevant to tube-to-flange arc-welded joints made from extruded and peak aged AlSi1MgMn alloy tested under constant and variable amplitude in-phase and out-of-phase combined bending and torsion loadings. © 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: welded joint; aluminium; fatigue; multiaxial; variable amplitude; Peak Stress Method 1. Introduction Welded structures made of aluminium alloys are widely used in lightweight engineering applications due to their high strength-to-weight ratio. Unfortunately, their susceptibility to fatigue failure poses significant challenges for engineers, since fatigue life prediction methods proposed by codes and standards [1 – 3] struggle to accurately account for the complexities introduced by real component geometries and in-service loads, the latter being typically Variable Amplitude (VA) and multiaxial. This study focuses on addressing this challenge by employing the Peak Stress Method (PSM) [4], an engineering method to rapidly assess the fatigue strength of arc welded joints by using linear elastic finite element analyses with relatively coarse mesh. Fatigue Design 2025 (FatDes 2025) Evaluating the fatigue strength of aluminium fillet-welded joints under multiaxial variable amplitude loading using the Peak Stress Method Luca Vecchiato a , Alberto Campagnolo a and Giovanni Meneghetti a , * a Department of Industrial Engineering, University of Padova, Via Venezia, 1 35131 Padova, Italy , a

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.2025.11.061