The focused heat input introduced by the laser beam leads to small melt pools, whose heat is quickly dissipated by already solidified material volume. Powder application and densification are repeated until the components are completed. The cross-sectional areas (slices) to be densified are calculated from 3D-Models of the desired components. Each applied powder layer is selectively densified by a high-energy laser beam. An AM process used in particular for metal processing is the Powder Bed Fusion-Laser Beam/Metal (PBF-LB/M) process, in which thin successive metallic powder layers are applied on a building platform. Furthermore, it allows the time-efficient production of highly customized components without using product-specific tools. ![]() Due to the layer-by-layer built-up, a resource-efficient production of highly complex, net-shaped components is possible, enabling the high potential for lightweight construction to be fulfilled. This is one of the reasons why interest in Additive Manufacturing (AM) processes has grown steadily in recent decades. In times of climate change and the steadily increasing scarcity of resources, special requirements are placed on the production of components concerning sustainability. Based on the knowledge obtained, a more detailed specification of the chemical composition of the type 316L stainless steel is recommended so that this steel can be PBF-LB/M processed to defect-free components with the desired mechanical and chemical properties. A limitation of the nickel equivalent of the 316L type steel is suggested for PBF-LB/M production. These cracks reduce the corrosion resistance as well as the elongation at fracture of the additively manufactured material that possesses a low chromium to nickel equivalent ratio of 1.0. This is related to a fully austenitic solidification, which occurs because of the low chromium to nickel equivalent ratio. As a main result, solid-state cracking could be observed in samples additively manufactured from the starting powder containing the maximum nickel content. The powder characteristics, the microstructure and defect formation, the corrosion resistance, and the mechanical properties were investigated as a function of the chemical composition of the powders used. The materials were processed by laser-based powder bed fusion (PBF-LB/M). The third material is a commercial powder with the chemical composition set in the middle ground of the allowed compositional range. ![]() Two starting powders are laboratory alloys, one containing the maximum allowed chromium content and the other one containing the maximum nickel content. Therefore, this influence is analyzed using three different starting powders. Nevertheless, the allowed compositional range impacts the microstructure formation in additive manufacturing and thus the properties of the manufactured components. ASTM A276 allows the chromium and nickel contents in 316L stainless steel to be set between 16 and 18 mass%, respectively, 10 and 14 mass%. This work aims to show the impact of the allowed chemical composition range of AISI 316L stainless steel on its processability in additive manufacturing and on the resulting part properties.
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