Determination of the Fatigue Behaviour of Laser Powder-Bed Fused AlSi10Mg Specimens Using Surface and Heat Treatments

The production of components using the powder bed fusion-laser based (PBF-LB) process opens up completely new possibilities in industry. Especially the geometry in freedom design shows clear advantages compared to conventional fabrication methods. Nevertheless, there are aspects that can cause a negative impact on the fatigue resistance behaviour of the components and thus, limit the advantages of this technology. The basis of this work is an extensive literature research on the topic of surface treatments for AlSi10Mg components to improve the fatigue strength. On this basis, post-treatments were carried out on vertically printed samples and their effects on the fatigue strength were analysed. Untreated samples were used as a reference, which was compared with different combinations of post-treatments such as laser polishing, T5 heat treatment, shot peening, vibratory grinding, and finishing. In order to investigate the fatigue strength, fatigue tests were carried out in the tensile threshold range at an R-value of 0.1. The fracture examination was carried out with the aid of a scanning electron microscope.