题目：Metal Additive Manufacturing (AM) : In-situ process monitoring and control in Directed Energy Deposition (DED)
Abstract:Metal additive manufacturing (AM) provides remarkable flexibility in geometry and component design. Metal powder-based AM can be classified into two types: powder-bed, known as Selective Laser Melting (SLM), and powder-blown, known as Directed Energy Deposition (DED). Major parameters affecting the AM process include, but are not limited to laser parameters, powder parameters, powder flow parameters in DED, laser path, environmental parameters, and the support structure design. This comprehensive set of process parameters creates opportunities to 1) introduce new materials in both SLM and DED, 2) create multi-materials, functionally-graded components, and 3) repair or modify existing components for enhanced functionalities in DED. At the same time, it also presents challenges for process control and process optimization, as parameters are not only adjustable in terms of means and variance but also variables in time and space. This talk will cover the development of the capability to perform temperature control and powder-flow control in DED to enable a structure with gradient material properties or hybrid materials.
Biosketch:Dr. Jihoon Jeong is a postdoctoral scholar in the mechanical engineering department at Northwestern University. Dr. Jeong received the B.S. and M.S. degrees from KAIST in 2009 and 2011, respectively, and the Ph.D. degree from the University of Texas at Austin (UT Austin) in 2020, all in mechanical engineering. Before his Ph.D. study, Dr. Jeong worked for Samsung SDI and KIST as a researcher conducting electrochemistry research specifically for Li-ion batteries and Fuel Cells. His academic interests extensively include metal additive manufacturing (AM), nano-/micro-scale thermal transport, and laser spectroscopy. Dr. Jeong has been focusing on metal AM research since he joined Northwestern University.