About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Advances in Powder and Ceramic Materials Science
|
Presentation Title |
Grain size Confinement of Secondary Phases in Entropy Stabilized Oxides |
Author(s) |
Alexander D. Dupuy, Julie M Schoenung |
On-Site Speaker (Planned) |
Alexander D. Dupuy |
Abstract Scope |
Entropy stabilized oxide (ESO) materials contain at least five oxide components, which form a single phase that is stabilized through entropy. A unique characteristic of ESOs is their reversible entropy-driven phase transformation, presenting an opportunity to produce oxide materials with controlled microstructures. In (CoCuMgNiZn)O, this transformation manifests as the formation of a Cu-rich tenorite secondary phase. We demonstrate experimentally that as-sintered grain size significantly influences the morphology of the secondary phase. Large grain sizes yield needle-shaped secondary phases within the grains. Smaller grain sizes confine the secondary phase, resulting in a transition in morphology. We also observe a region adjacent to the grain boundary that is depleted in secondary phase. This depletion region becomes more prevalent at smaller grain sizes, leading to the observed confinement effect. The confinement effect follows a simple geometric model, allowing for the secondary phase morphology in (CoCuMgNiZn)O to be predicted based on grain size. |
Proceedings Inclusion? |
Planned: |
Keywords |
Ceramics, Phase Transformations, |