Fatigue strength assessment of as built AlSi10Mg manufactured by SLM with different build orientations

This study investigated the effects of the 'as-built' condition on the fatigue properties of an AlSi10Mg aluminium alloy manufactured by Selective Laser Melting (SLM) in different orientations. The results showed a moderate correlation between defects/surface features at the fracture origin and the roughness measurements. On the other hand, a fatigue strength analysis based on the size of features at fracture origin and residual stress just below the surface proved to be successful. Although considering the synergistic effect of different variables increased the scatter in fatigue life data points, a fatigue strength model including short crack effect and residual stresses made it possible to estimate the EIFS close to the real critical features. Results for life prediction models based on EIFS showed that 87% of the estimated number of cycles to failure are within a factor of 0.5-2 with respect to the experimental number of cycles to failure.