Role of Laser Exposure, Rotation and Scan Pattern on the Densification Process of LPBF Samples

The development of laser powder bed fusion technique, over the last 20 years, has led new machine producers to appear in this market. Each machine has several parameters to be optimized: most of the scientific papers are focused on parameters related to the volumetric energy density such as laser power, scanning speed, hatching distance and layer thickness, in order to obtain the highest possible part density. By contrast, scan pattern, exposure and rotation between layers are rarely considered and, often, selected as recommended by the machine producers. The main goal of this work was the analysis of the key-role of scanning strategy in terms of scan pattern, exposure and rotation on the densification process of LPBF samples; their correlation with volumetric energy density, microstructure and production time was also evaluated.