@misc{MaiwaldSchmailzlHierl, author = {Maiwald, Frederik and Schmailzl, Anton and Hierl, Stefan}, title = {Thermo-mechanical computation of weld seam geometry in laser transmission welding}, series = {Applied Research Conference - ARC 2017, 7 July 2017, M{\"u}nchen}, journal = {Applied Research Conference - ARC 2017, 7 July 2017, M{\"u}nchen}, editor = {Klippel, Clemens and Mottok, J{\"u}rgen and Reichenberger, Marcus}, publisher = {pro Business GmbH}, address = {Berlin}, language = {en} } @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} }