PSI - Issue 83

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ScienceDirect

Procedia Structural Integrity 83 (2026) 229–238

© 2026 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 ESIAM26 organizers Keywords: Additive Manufacturing; Aluminium alloy; Fatigue; Surface roughness; Heat treatment; Miniature specimens; Build orientation Abstract Laser Powder Bed Fusion (PBF-LB) allows cost-effective weight reduction through high-resolution net-shaped manufacturing of complex geometries. The resultant topology-optimized components often manifest features with different thicknesses and orientations that exhibit different mechanical and fatigue properties owing to the gradient in both bulk material properties and surface roughness. Four size-orientation combinations of PBF-LB AlSi10Mg specimens are investigated in their as-built surface condition, and a characterization encompassing their surface roughness and fatigue performance is conducted after T6 solution annealing and aging heat treatment to neutralize differences in fatigue behavior that stem from micro and mesostructural anisotropy. T6 heat-treated specimens with different build orientations exhibited identical tensile behavior before fracture, but showed a decrease in Elongation at Break (EaB) with decreasing build angles, consistent with the increase in surface roughness. Miniature specimens demonstrated a superior fatigue performance to that of standard counterparts, exhibiting a 5% increase in the collective orientation-independent fatigue limit as well as 6% lower scatter. The increase in surface roughness that accompanied the decrease in build angle determined a reduction in fatigue life in the case of standard specimens, while the miniature horizontal orientation showed comparable behavior to the 45°, despite its significantly higher roughness. The fourth European Conference on the Structural Integrity of Additively Manufactured Materials (ESIAM26) Fatigue Performance of T6 Heat-treated PBF–LB AlSi10Mg with As-built Surface at Different Sizes and Build Orientations Ahmad Issmail, Nima Razavi * Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology, Richard Birkelands vei 2B, 7491 Trondheim, Norway

* Corresponding author. E-mail address: nima.razavi@ntnu.no

2452-3216 © 2026 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 ESIAM26 organizers 10.1016/j.prostr.2026.07.026