Effect of process parameters on tensile and impact strength properties of AISI 316L stainless steel fabricated via laser-powder bed fusion

Recent advances in the production of metallic components via Laser-Powder Bed Fusion (L-PBF) have attracted considerable interest, promising to achieve properties comparable to those of conventional manufacturing while reducing production time and costs. Among the materials suitable for L-PBF, austenitic stainless steels, such as the AISI 316L one, stand out due to their versatility across various industrial applications. The selection of process parameters including laser power, hatch spacing, scan speed and layer thickness strongly influences the final properties of printed parts. The present work aims to evaluate the metallurgical and mechanical features of L-PBF AISI 316L samples produced with different layer thicknesses (25, 50 and 100 µm) and according to two building directions, i.e., horizontal (xy) and vertical (xz) with respect to the building platform. Experimental investigations including density measurements, microstructural analyses through optical and scanning electron microscopes, tensile and instrumented Charpy impact tests were performed. The relationship between the employed layer thickness and both tensile strength and impact toughness was also assessed. By selecting proper process parameters such as laser power, scanning speed and layer thickness within a specific range of values, the resulted laser density energies promote good-quality of the printed samples with excellent mechanical properties.