Computational analysis of the thermo-hydrodynamic transport processes during substrate re-melting in laser powder bed fusion of AlSi10Mg

Abstract

As a precursor to the development of a full-scale computational model for analysis of the thermal-hydrodynamic transport phenomena during laser powder bed fusion of AlSi10Mg, a model for substrate re-melting has been developed. Material evaporation has also been included in the model as a medium for energy loss. While the melt pool temperatures and dimensions reflected a typical relationship with the process parameters described in the literature, the results agreed very well with the in-house experimental data too. The study also focused on unveiling the individual effects of the melt pool hydrodynamics and material evaporation on the melt pool, and it was observed that the former had very little effect on the results compared to the latter. Parametric analysis for the melting mode identification and melt track stability analysis revealed that the melting happened in conduction mode even at the highest linear energy density and remained stable throughout the parameter window. Both findings were proved true from the experimental observation.