Abstract
While extensive research on laser powder bed fusion has focused on optimizing process parameters to improve the performance of manufactured parts, the critical role of effective spatter particle removal in mitigating defects during manufacturing has not received commensurate attention. To address these issues, this study investigates the influence of a key parameter in the atmosphere protection system, namely, airflow velocity, on part performance. Methodologically, a combined approach of numerical simulation and experimental methods was employed to examine in detail the effect of airflow velocity on spatter removal efficiency and its corresponding contribution to the enhancement of formed Inconel 718 part quality. First, Computational Fluid Dynamics-Discrete Phase Model simulations identified an optimal airflow velocity of 0.57 m/s. Subsequently, experimental observations using a high-speed camera system revealed that velocities below 0.6 m/s led to spatter redeposition, resulting in pore and defect formation, whereas velocities exceeding 0.6 m/s increased spatter size and reduced molten-pool stability. The simulation and experimental results are consistent, demonstrating that an appropriate airflow velocity can effectively suppress defects and thereby improve the quality of the fabricated components. This research provides a viable pathway for significantly enhancing the mechanical properties of laser powder bed-fused Inconel 718.