Correlation of Surface Topography with Fatigue Life and Failure Location in Additively Manufactured AlSi10Mg via Computed Tomography

The fabrication of AlSi10Mg components via PBF-LB results in the formation of porosity and a rough surface topography. Depending on the relative position to the inert gas flow, the geometry of the component and other factors, these features are also distributed inhomogeneously, which has an adverse effect on fatigue performance. Computed tomography enables the measurement of the entire component surface, making it possible to locate failure critical spots on component surfaces. In this work, surfaces of additively manufactured components are analyzed by a novel method using computed tomography. This allows the visualization of the variation in roughness and near-surface porosity, which in turn facilitates the identification of failure critical spots and their comparison to real failure spots. Furthermore, the location of the failure critical spot can be predicted in 50% of the cases, while a correlation with fatigue life is found for low stress amplitudes.