About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
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Additive Manufacturing: Materials Design and Alloy Development V – Design Fundamentals
|
Presentation Title |
Oxide Coarsening Effects during Melt-based Additive Manufacturing -- Physics-based Modeling |
Author(s) |
Roger Hou, Timothy Stubbs, Aijun Huang, Zachary C. Cordero |
On-Site Speaker (Planned) |
Roger Hou |
Abstract Scope |
Oxide dispersion-strengthened (ODS) superalloys incorporate nano-scale oxide dispersoids that inhibit dislocation motion, imparting exceptional high temperature creep resistance for the most demanding structural applications. There is current interest in using metal additive manufacturing (AM) techniques, e.g., laser powder bed fusion (LPBF), to directly form net-shaped ODS components. However, a major concern with AM of ODS alloys is that the dispersoids will coarsen, agglomerate, and lose their efficacy during the brief melt cycle. Here we present a physics-based model of such coarsening phenomenon which builds upon the classical Ostwald ripening solution, with key inputs determined via thermofluid and thermochemical models. Predictions of oxide size are validated through comparison with experimental measurements on AM MA754, manufactured through LPBF and DED. Finally, two competing mechanisms (particle-pushing-induced agglomeration versus convection-aided runaway coarsening) are shown to explain experimental observations of large oxide slag inclusions. |
Proceedings Inclusion? |
Planned: |
Keywords |
Additive Manufacturing, Copper / Nickel / Cobalt, Solidification |