|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Additive Manufacturing of Metals: Applications of Solidification Fundamentals
||Controlling Additive Manufacturing Processes with Magnetic Fields
||Andrew Kao, Teddy Gan, Xianqiang Fan, Catherine Tonry, Ivars Krastins, Peter D Lee, Koulis Pericleous
|On-Site Speaker (Planned)
Strong thermal gradients in additive manufacturing (AM) form thermoelectric currents in the melt pool. Applying an external magnetic field generates a Lorentz force driving flow, a phenomenon known as Thermoelectric Magnetohydrodynamics (TEMHD). Theoretical studies by the authors have shown that TEMHD can significantly alter the melt pool dynamics and consequently, solute redistribution and microstructure evolution.
In this work the effect of the magnetic field is investigated combined with scanning strategies, such as hatching. The results show that TEMHD has the potential to alleviate defects in AM for example disrupting epitaxial growth.
The study uses a coupled meso-micro approach. On the meso-scale an enthalpy method resolves the electromagnetic, thermal and hydrodynamic problem. The CA method is used to predict the microstructure.
The change in melt pool shape was experimentally validated using correlative imaging, including fast infra-red and optical imaging. Metallography was performed to quantify the impact on grain size and microstructure.