The effect of beam pulsing on laser beam processing of Ti-6Al-4V using a prototype laser additive manufacturing platform

Recent advancements in additive manufacturing have highlighted the limitations of conventional beam motion techniques in manipulating cooling rates and melt pool dynamics. This pursuit has led to the investigation of alternative approaches including multi-beam motion, beam oscillation, beam shaping and beam pulsing, all aimed at refining control over the manufacturing process. Notably, recent research emphasizes the potential benefits of operating in a keyhole regime during laser powder bed additive manufacturing. The primary focus of this research is to provide preliminary insights for our industrial partner (CANMORA TECH Inc.) on the feasibility of beam pulsing as a mechanism for controlling microstructure and particularly defects when melting under conditions that lead to keyholing. The aim is to achieve this control by dynamically adjusting the beam's position over time and modulating power within different duty cycles and frequencies in Laser Powder Bed Additive Manufacturing. The laser tracks are built under these varied pulsing conditions and the results of heat transfer modelling will be presented to predict the impact of pulsing on melt pool geometry.