Fatigue response of AlSi10Mg by laser powder bed fusion: influence of build orientation, heat, and surface treatments

The aim of this study is to analyze how the fatigue behavior of AlSi10Mg by laser powder bed fusion is affected by build orientation, heat, and surface treatments. A three-by-three factorial plan has been arranged for this purpose. Particularly, regarding the heat treatment, three levels were considered (as built, age hardening, and stress relief); whereas, for the surface treatment, three levels were investigated (micro-shot-peening, micro-shot-peening plus fine blasting, and machining and lapping following laser powder bed fusion). Regarding the build orientation, the specimens were manufactured using three different build orientations (0 degrees, 45 degrees, and 90 degrees). The obtained data have been statistically analyzed by a three-factor ANOVA-based method. The results, supported by fractographic and micrographic microscopy analyses, indicate that the age-hardening treatment yields the maximum benefits, whereas stress relief may even have a detrimental effect. As for surface treatments, a positive influence of shot-peening has been found.