Fatigue Properties of Powder Bed Fused Inconel 718 in As-Built Surface Condition

The aim of this study was to investigate the fatigue properties of Selective Laser Melted (SLM) processed Inconel 718 (IN718). The joint research activity between the European Space Agency and the company Renishaw, chose IN718 for its suitability in applications for launcher engine components and for Additive Manufacturing (AM) processing. The high-cycle fatigue properties of vertically and horizontally built specimens in as-built condition were investigated and a stress-life (S-N) curve constructed. The fatigue specimens were characterized by X-Ray Computed Tomography (XRCT) and the fracture surfaces analysed by Scanning Electron Microscopy (SEM). The analysis performed shows similar fatigue properties of vertically and horizontally built specimens below 106 cycles, despite significant differences in surface roughness.