| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
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| Symposium
|
Microstructural Evolution and Material Properties Due to Manufacturing Processes: A Symposium in Honor of Anthony Rollett
|
| Presentation Title |
Experimental and Numerical Studies on Melt Pools in Metal Additive Manufacturing |
| Author(s) |
Yoon Suk Choi, Seulbi Lee, Jaewoong Kim |
| On-Site Speaker (Planned) |
Yoon Suk Choi |
| Abstract Scope |
Inspired by Professor Rollett’s pioneering work on high energy X-ray based in-situ observation of melt pools during metal additive manufacturing, the present talk deals with experimental and numerical studies on melt pools processed by laser powder bed fusion (PBF) and direct energy deposition (DED), particularly focused on the following aspects:
(1) parametrization of the heat source model to predict melt pool geometries (the width and depth) of Alloy 718 with different PBF process conditions using thermal finite element method (FEM) simulations and the physical implication of the result;
(2) classification of micro-cracks formed along (or near) the melt pools of TiAl during the PBF process, and the electron microscopy and thermal-mechanical FEM analysis to understand the micro-crack formation behaviors;
(3) clarification on the micro-cracking mechanism of medium carbon steel melt pools deposited on gray cast iron using DED process.
In the first topic, the parametrization of the laser heat source model allowed us to deduce physically meaningful profiles of the laser penetration depth and absorptivity, as a function of a modified energy-density parameter, which were related with the melt pool depth and width profiles, respectively. In the second topic, different micro-crack patterns of TiAl melt pools were categorized under different PBF process conditions. The electron microscopy aided with focused ion beam (FIB) and the FEM-based thermal stress analysis were performed to clarify the nature and the cause of those micro-cracks. In the last talk, the formation of micro-cracks of medium carbon steel melt pools deposited on gray cast iron by the DED process was extensively investigated using electron microscopy and chemistry analysis. Finally, the talk wraps up with mentioning how Professor Rollett’s pioneering work helped understanding melt pool physics of the present studies experimentally and numerically. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Additive Manufacturing, Characterization, Modeling and Simulation |