|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Additive Manufacturing: Advanced Characterization with Synchrotron, Neutron, and In Situ Laboratory-scale Techniques II
||In Situ Characterization of Laser-based Metal Additive Manufacturing by Detection of Thermal Electron Emission
||Philip Depond, John C. Fuller, Saad Khairallah, Justin R. Angus, Gabe Guss, Manyalibo Matthews, Aiden A. Martin
|On-Site Speaker (Planned)
||Aiden A. Martin
Current diagnostic methods for laser powder bed fusion additive manufacturing (AM) capture optical images, X-ray radiographs, or measure the emission of thermal or acoustic signals from the component. Here we discuss a methodology based on the thermal emission of electrons - thermionic emission - from the metal surface during laser heating. Experimental studies show increases in thermionic emission are correlated to laser scanning conditions that give rise to pore formation and regions where surface defects are pronounced. State of the art multi-physics simulations corroborate the relationship between increased melt depression depth and thermionic signal including perturbations in the melt pool that lead to material ejection (i.e., spatter). The information presented here is a critical step in furthering our understanding and validation of laser-based metal AM and demonstrates that the collected thermionic signals can be incorporated into conventional data collection schemes and processing methods.