| About this Abstract |
| Meeting |
2023 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Stability in Extreme Environments
|
| Presentation Title |
Precipitate Evolution in Post-AM Heat Treated and HFIR Irradiated Inconel 718 Alloys |
| Author(s) |
Stephen Taller, Lukas Metzger, Matthew Lynch |
| On-Site Speaker (Planned) |
Stephen Taller |
| Abstract Scope |
Ni-based superalloys are a candidate alloy class for high temperature applications because of their intrinsic resistance to creep, their adequate resistance to corrosion and their high strength gained through secondary phases. Because nickel alloys work harden extensively, additive manufacturing can produce geometrically complex components traditionally unavailable through conventional machining. Three heat treatments of additively manufactured superalloy 718, two with distinct mixtures of δ ,γʹ and γʹʹ precipitates, and one completely homogenized, were irradiated in the High Flux Isotope Reactor (HFIR) nominally to 2 DPA at either 300°C or 600°C to represent current and advanced reactor temperatures. The microstructure was characterized for precipitates, cavities, and dislocations using Scanning Transmission Electron Microscopy and Energy-Dispersive X-ray Spectroscopy. Molecular statics and dynamics calculations of Ni-Nb precipitate-defect interactions at multiple temperatures informed a rate theory Nelson-Hudson-Mazey based model using calculated sink strengths of each microstructural feature to interpret the observed precipitate sizes and densities. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Characterization, Phase Transformations, Environmental Effects |