Influence of process parameters and wall thicknesses on the properties of tool steel 1.2709 (X3NiCoMoTi18-9-5) processed by Selective Laser Melting

Selective Laser Melting (SLM) has gained significant importance as a manufacturing process for complex geometries and high-precision components. For tool steels such as 1.2709, which are valued for their high strength and hardness, optimizing the process parameters is essential to achieve the desired mechanical properties and minimize defects. The ability to control factors like wall thickness and energy density is essential for producing thin-walled components with high structural integrity and reliability. In this study, the influence of the selected process parameter and wall thickness on the fabrication of tool steel 1.2709 by SLM was investigated. The tool steel was processed using two different process parameters and eleven wall thicknesses ranging from 0.2 to 1.0 mm. The two process parameters V1 (87 J/mm³) and V2 (48 J/mm³) differ significantly in their energy density. The specimens were examined for their final wall thickness. Furthermore, the influence of the process parameter and the wall thickness on the mechanical properties, the defects and the microstructure were determined. The investigations revealed a fine dendritic microstructure in the as-built condition. Depending on the process parameter, the mechanical properties are weakened by the porosity observed in thinner wall thicknesses.