In this study, multiaxial fatigue behaviour of IN718 thin walls obtained by laser powder bed fusion is investigated. Tubular thin-walled specimens of various thickness and orientation were subjected to tension, torsion and proportional loadings. Fractographies analysis showed a crystallographic fracture initiation for all specimens. While vertical specimens of thickness higher than 400 μm exhibits similar behaviour to bulk specimens, 200 μm specimens show lower endurance limit, due to large geometrical variations and increased influence of porosities.

Keywords: Multiaxial fatigue, Thin walls, Lattices, IN718