Archive | 2021
Laser absorptivity approximation in the heat transfer modeling of laser powder-bed fusion
Abstract
Laser Powder-Bed Fusion (LPBF) additive manufacturing is a relatively new manufacturing technique in which geometrically complex parts can be made by selectively melting layers of powder. Finite element simulations of heat transfer in LPBF are widely investigated and employed to accurately simulate the manufacturing process. One of the most critical considerations during numerical modeling is the laser absorptivity since the laser absorption is influenced by powder size and its distribution and by the dynamic melt-pool surface morphology. In this work, a simple laser-absorptivity approximation model is proposed. Besides, varied anisotropic thermal conductivity is also considered. In order to validate the approximation model, a three-dimensional finite element model with a volumetric heat source is employed to simulate single tracks printed using LPBF. The numerical model is used to predict the melt-pool width and depth and shows good agreement with experimental measurements.