Anisotropic fatigue properties of Alloy 718 manufactured by Electron Beam Powder Bed Fusion. (December 2020)

• Record Type: Journal Article
• Authors: Balachandramurthi, Arun Ramanathan; Moverare, Johan; Hansson, Thomas; Pederson, Robert
• Is Part Of: International journal of fatigue. Volume 141(2020)
• Publication Date: 2020-12
• Subjects: Low cycle fatigue -- Alloy 718 -- Electron beam powder bed fusion -- Anisotropy -- Additive manufacturing; Materials -- Fatigue -- Periodicals; Materials -- Fatigue; Periodicals; 620.1122
• DOI: 10.1016/j.ijfatigue.2020.105898
• Languages: English
• ISSNs: 0142-1123

Abstract

Highlights: LCF behaviour of post-treated EB-PBF Alloy 718 is anisotropic. Parallel direction has better LCF performance than transverse direction. Strain vs. life relationship is not affected by post-treatments. Pseudo-elastic stress vs. fatigue life approach can potentially handle anisotropy. Abstract: In this study, Alloy 718 specimens manufactured by Electron Beam Powder Bed Fusion process are subjected to two different post-treatments to have different microstructural features. Low cycle fatigue testing has been performed both parallel and transverse to the build direction. EB-PBF Alloy 718 exhibits anisotropic fatigue behaviour; the fatigue life is better along the parallel direction compared to the transverse direction. The anisotropy in fatigue life is related to the anisotropy in the Young's modulus. The pseudo-elastic stress vs. fatigue life approach is presented as a potential solution to handle anisotropy in fatigue life assessment of additively manufactured engineering components.