PSI - Issue 76

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ScienceDirect

Procedia Structural Integrity 76 (2026) 43–49

© 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 FDMD 2025 chairpersons Keywords: Fatigue crack growth; porosity; AlSi10Mg; shot peening; stress relief. Abstract Laser Powder Bed Fusion (L-PBF) enables the 3D printing of components in Aluminium alloys, widely used high-performance engineering applications, whereby it is fundamental the understanding of in-service fatigue behaviour. Current paper is focused on the fatigue crack propagation of AlSi10Mg aluminium alloy using CT specimens. The tested material conditions included as-built (AB), as-built shot-peened (AB+SP), stress-relieved (SR) and stress-relieved shot-peened (SR+SP), loaded in mode I. The purpose of the work was to understand the correlation between post-built treatments, residual stresses, porosity defect levels and fatigue crack growth (FCG), including transient regime after overload applications. The porosity levels were obtained by tomography technique. The residual stress relief and their subsequent stabilization were the main mechanisms responsible for improving the fatigue crack growth resistance. The as-built shot-peened condition showed minimal influence on FCG rates in the near-threshold regime but did increase the threshold value. At higher ΔK values, the FCG behaviour of as -built and as-built shot-peened specimens was similar, and for stress-relieved specimens, shot-peening treatment provided no notable benefit, as FCG rates for stress-relieved and stress-relieved shot-peened conditions were comparable. 5th International Symposium on Fatigue Design and Material Defects FDMD 2025 Effect of shot peening and heat treatments on the fatigue crack propagation on AlSi10Mg alloy specimens produced by L-PBF R. Fernandes a , J.S. Jesus a , L. P. Borrego a,b *,J.A.M. Ferreira a , R. Branco a , J.D.M. Costa a a Univ Coimbra, Centre for Mechanical Engineering, Materials and Processes (CEMMPRE), ARISE, Department of Mechanical Engineering, P 3004 516 Coimbra, Portugal b Polytechnic University of Coimbra, Coimbra Institute of Engineering, Department of Mechanical Engineering, Rua Pedro Nunes - Quinta da Nora, 3030-199 Coimbra, Portugal

* Corresponding author. Telem.: +351 962560101. E-mail address: borrego@isec.pt

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 FDMD 2025 chairpersons 10.1016/j.prostr.2025.12.285