Numerical Analysis of the Melt Pool Kinetics in Selective Laser Melting Based Additive Manufacturing of Thermoelectric Powders Available to Purchase

Thermoelectric generators convert heat energy to electricity and can be used for waste heat recovery, enabling sustainable development. Selective Laser Melting (SLM) based additive manufacturing process is a scalable and flexible method that has shown promising results in manufacturing high zT Bi₂Te₃ material and is possible to be extended to other material classes such as Mg₂Si. The physical phenomena of melting and solidification were investigated for SLM-based manufacturing of thermoelectric (Mg₂Si) powders through comprehensive numerical models developed in MATLAB. In this study, Computational Fluid Dynamics (CFD)-based techniques were employed to solve conservation equations, enabling a detailed understanding of temperature evolution within the molten pool. This approach was critical for optimizing processing parameters in our investigation, which were also used for printing the Mg₂Si powders using SLM. Additionally, a phase field-based model was developed to simulate the directional solidification of the Mg₂Si in MATLAB. Microstructural parameters were studied to correlate the effects of processing parameters to the microstructure of Mg₂Si.