In additive manufacturing, large temperature variations lead to the generation of thermoelectric currents. When subject to an external magnetic field these currents interact to form a Lorentz force driving flow. This Thermoelectric Magnetohydrodynamic (TEMHD) flow competes with the inherent Marangoni flow influencing heat and mass transport. TEMHD flow is highly dependent on the orientation and strength of the magnetic field, acting as a useful control parameter. This coupled system is solved using the bespoke numerical code TESA (ThermoElectric Solidification Algorithm), that resolves the melt pool morphology and fluid dynamics using an Enthalpy approach coupled to Lattice-Boltzmann methods. This is then further coupled to a Cellular Automata based approach to predict grain and dendritic evolution. The simulation results show that TEMHD flow can be of the same order of magnitude as Marangoni flow and has the potential to control the melt pool morphology and dynamics with different configurations leading to either a shallow wide pool, a deep narrow pool or even promoting a cross-path deflection. The resulting microstructure simultaneously resolved shows that changes to the melt pool flow can have a significant impact on disrupting defects such as, epitaxial growth

Moderated by: Hani Henein / Mark Jolly