Modelling of heat transfer in powder bed based additive manufacturing process using Lattice Boltzmann Method

Abstract

One of the most promising additive manufacturing techniques is selective laser melting process. It is a complex process, which involves physical phenomena, such as absorption of the laser beam in the powder bed, melting and re-solidification, diffusive and radiative heat transport in the powder, diffusive and convective heat transport in the melt pool, gravity effects, etc. In this study, a two-dimensional lattice Boltzmann model is formulated to investigate melting of a uniformly packed powder bed under the irradiation of laser beam during the selective laser melting process. In the model, phase change of individual powder particle is considered mesoscopically. The results give an insight into the details of heat transfer and melting in the powder bed and formation of the mushy zone. These mesoscopic results can be useful to set parameters of the powder bed in additive manufacturing processes. The model developed can be applied to any powder bed based additive manufacturing process.