Optimization of process parameters and build orientation effects on the tensile properties of Laser-Powder Bed Fusion (L-PBF) AlSi10Mg components

Additive Manufacturing (AM) has revolutionized industrial production, particularly in the aerospace, biomedical, and automotive sectors. Among AM technologies, Laser-Powder Bed Fusion (L-PBF) is a widely adopted process for fabricating metallic components due to its ability to produce near-net-shape parts with tailored mechanical properties. However, optimizing SLM process parameters remains a challenge, as factors such as layer thickness, scanning strategy, build orientation, position on the build plate, and laser beam overlap conditions significantly influence the mechanical performance of printed components. This study investigates the combined effects of these key parameters on the tensile and microhardness properties of SLM-fabricated AlSi10Mg components. Results show that reducing layer thickness from 60 to 30 µm increases both tensile strength and elongation at break, owing to finer microstructures and reduced internal defects. Samples built with 0° orientation exhibit a higher Young’s modulus but lower ductility compared to 90°-oriented ones, while the build plate position affects microhardness, with samples in the Z1 zone showing the highest values. Overlapping scan strategies lead to increased residual stresses and microstructural heterogeneity, particularly reducing ultimate tensile strength (UTS) and elongation in 0°-oriented samples. In contrast, 90°-oriented samples demonstrate a finer microstructure that mitigates overlap-induced embrittlement. Furthermore, the UTS/microhardness (HK) ratio decreases under overlapping conditions, indicating a decline in mechanical reliability. These findings provide quantitative insights into how process-induced microstructural inhomogeneities affect mechanical performance, offering clear guidelines for balancing production speed and structural integrity in the industrial-scale manufacturing of AlSi10Mg components.