Effects of spatter deposition and build location in laser powder bed fusion of maraging steel parts

Additive manufacturing effective implementations require knowledge about how process planning can influence product outcomes. Tuning non-traditional parameters of laser powder bed fusion (L-PBF) manufacturing, like better part location in the build platform considering the manufacturing atmosphere and projected laser inclination, may have consequences for the final product. However, understanding the material behavior derived from the location selection still needs investigation, which would provide valuable contributions to these process applications. This study investigated how gas flow, spatter ejection, and laser inclination on L-PBF affect maraging steel integrity regarding microstructure and mechanical performance joining experimental and simulation tools. Microscopy techniques, tensile tests, nanoindentations, and the simulation of the gas flow interaction with spatters allowed identifying preferential spatter deposition regions based on the gas flow and its potential consequences on the studied properties of maraging samples manufactured in three build platform locations. For instance, the location less prone to spatter deposition provided 12 to 16% lower microhardness than the other evaluated locations. This observation indicates processing parameters that can be used for managing L-PBF issues. So, these findings show the importance of considering the build location and relative gas flow direction during the L-PBF planning in addition to more trivial parameters.