| About this Abstract |
| Meeting |
2023 TMS Annual Meeting & Exhibition
|
| Symposium
|
Refractory Metals 2023
|
| Presentation Title |
High Entropy Rare-earth Oxide (HERO) Coatings for Refractory Alloys |
| Author(s) |
Kristyn Ardrey, Mackenzie Ridley, Prasanna Balachandran, Bi-Cheng Zhou, Patrick Hopkins, Elizabeth J. Opila |
| On-Site Speaker (Planned) |
Elizabeth J. Opila |
| Abstract Scope |
A new coating concept for refractory alloys, described here, utilizes high entropy rare earth oxide (HERO) mixtures to achieve requisite coating properties. The C-type RE2O3 have cubic crystal structures and are desired for a good thermal expansion match to refractory alloys. RE2O3 are high-temperature steam-stable and readily form apatite and other silicate barrier layers during reaction with molten siliceous debris. Oxygen diffusivity in Y2O3 is orders of magnitude lower than that in yttria stabilized zirconia. Combinations of RE cations in RE2O3 with large mass and size variation reduce thermal conductivity due to increased phonon scattering. Refractory metals and RE2O3 have a stable interface due to the significantly higher stability of RE2O3 relative to refractory metal oxides. In this presentation, proof of concept results for each of these required properties will be presented. Multicomponent RE2O3 mixtures that simultaneously optimize coating properties for refractory alloys will be described. |
| Proceedings Inclusion? |
Undecided |
| Keywords |
Environmental Effects, Ceramics, |