Measuring, Modeling, and Controlling Blue-Laser Directed Energy Deposition of Copper and Multi-Materials
Date: October 2, 2026; Time: 2:30 PM Location: PWEB 175
Abstract: Blue laser directed energy deposition (DED) offers a breakthrough approach for additive manufacturing of highly reflective metals such as copper and its alloys. Unlike traditional infrared lasers with poor absorptivity (<10%), blue lasers achieve absorption rates above 60%, enabling efficient melting and stable deposition. Yet, producing consistent, defect-free components remains challenging due to the sensitivity of melt pool dynamics, fluctuations in powder delivery, and complex laser–material interactions. This talk presents a multi-sensor monitoring and process control framework specifically developed for blue-laser DED. The approach integrates in-situ multispectral imaging (MSI), real-time photodiode sensing, and global thermal history mapping via infrared (IR) imaging to capture complementary process signatures across spatial and temporal scales. Through data fusion, these signals are correlated with part-quality indicators, including track geometry, surface morphology, and porosity. Building on these insights, we demonstrate closed-loop control strategies capable of actively regulating melt pool temperature and geometry in real time. The results highlight the promise of sensor fusion in advancing defect-minimized additive manufacturing of copper and other reflective metals, with broader implications for multi-material builds and functionally graded structures.
Biographical Sketch: Dr. Jihoon Jeong is an Assistant Professor in the Wm Michael Barnes ’64 Department of Industrial and Systems Engineering at Texas A&M University. His research spans laser-based metal additive manufacturing (AM) and semiconductor packaging, with particular emphasis on blue-laser directed energy deposition of copper and multi-materials, real-time process monitoring and control, in-situ characterization using non-destructive methods such as thermography and laser spectroscopy, and physics-informed machine learning for thermal modeling. Prior to joining Texas A&M in 2024, he was a Postdoctoral Scholar at Northwestern University (2021–2023), working on metal AM. He received his B.S. and M.S. from KAIST in 2009 and 2011, respectively, and his Ph.D. from The University of Texas at Austin in 2020, all in mechanical engineering. Before his doctoral studies, he conducted research on Li-ion batteries and fuel cells at Samsung SDI and the Korea Institute of Science and Technology (KIST). Dr. Jeong has authored more than 40 journal articles and holds 12 patents. His recognitions include the Young Researcher Award at PRESM 2024, the Outstanding Paper in Manufacturing Processes Award at NAMRC 53 (2025), and the 2026 Outstanding Early Career Award from the IISE Manufacturing and Design Division.