Numerical and experimental investigation into powder entrainment and denudation phenomena in laser powder bed fusion process

Abstract

This paper investigates the formation and dynamics of the powder entrainment and denudation phenomena in the L-PBF process. A new three-dimensional (3D) coupled Computational Fluid Dynamics (CFD) – Discrete Element Method (DEM) model is constructed to simulate not only the powder entrainment and powder denudation effects, but also the powder absorption effect of the moving melt-pool. Numerical simulations are performed to simulate the denudation width in single-track L-PBF processing. It is clearly found that significant difference between the denudation widths is obtained for different metal vapor ejection angles. To enhance the accuracy of the simulated denudation zone, a pre-defined virtual moving melt-pool is incorporated to consider the powder absorption effect of the moving melt-pool. The simulated results qualitatively have a good agreement with both self-conducted experiments and published experimental results.