@misc{MeisnerKaftiranisMaiwaldetal., author = {Meisner, Dennis and Kaftiranis, Nikitas and Maiwald, Frederik and Rapp, Petra and Hierl, Stefan}, title = {Enhancing Layer Adhesion in Material Extrusion AM with Adaptive Laser Preheating Integrated in Printhead}, series = {LiM Conference 2025, Lasers in Manufacturing, June 23 - 26, 2025, Munich, Germany}, journal = {LiM Conference 2025, Lasers in Manufacturing, June 23 - 26, 2025, Munich, Germany}, publisher = {Wissenschaftliche Gesellschaft Lasertechnik und Photonik e.V.}, abstract = {Material extrusion is a widely used AM process and is gaining more acceptance in industry applications due to its material variety, flexibility, and low cost. However, its usage is limited by a process-related anisotropy caused by insufficient interlayer bonding due to reduced temperature in the process zone. To enhance layer adhesion, an adaptive laser preheating system is integrated in a conventional printhead around the extrusion nozzle. The setup with eight fiber coupled diode laser allows preheating in feed direction and investigation of various intensity profiles. The article describes the experimental setup and significant improvements achieved. Laser preheating with different intensity distributions (spot, sickle or ring shaped) show an incasement of up to 85 \% of the mechanical properties in the build-up direction. However, due to the additional energy input by the laser, controlled cooling of the workpiece becomes a crucial factor and is investigated as well.}, language = {en} } @inproceedings{MeisnerForstnerKaftiranisetal., author = {Meisner, Dennis and Forstner, Lukas and Kaftiranis, Nikitas and Hierl, Stefan}, title = {Investigation of process improvements through laser preheating in extrusion-based additive manufacturing process}, series = {Lasers in Manufacturing Conference (LIM 2023), 26. Juni bis 29. Juni 2023, M{\"u}nchen}, booktitle = {Lasers in Manufacturing Conference (LIM 2023), 26. Juni bis 29. Juni 2023, M{\"u}nchen}, publisher = {Wissenschaftliche Gesellschaft Lasertechnik und Photonik e.V. (WLT)}, pages = {10}, abstract = {Fused layer modeling (FLM) is widely used and is gaining more acceptance in the industry mainly due to its material variety and low costs. However, the usage is limited by a process-related anisotropy of the produced parts. The strength and ductility of the printed parts are significantly lower in the build-up direction than perpendicular to it. This is caused by insufficient interlayer bonding resulting from a reduced surface temperature in the process zone. To overcome this problem, a diode laser is integrated into the conventional FLM process to increase the surface temperature between the already printed surface and the newly applied substrate directly at the deposition zone. The investigations carried out show a significant improvement in the mesostructure, as well as a clear reduction in the anisotropy of the printed test specimens.}, language = {en} }