About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
|
Advances in Powder and Ceramic Materials Science
|
Presentation Title |
Multiscale Phase Homogeneity in Bulk (CoCuMgNiZn)O High Entropy Oxides |
Author(s) |
Alexander D. Dupuy, Mohammed Reda Chellali, Xin Wang, Horst Hahn, Julie M Schoenung |
On-Site Speaker (Planned) |
Alexander D. Dupuy |
Abstract Scope |
High entropy oxide (HEO) materials contain at least five oxide components, which form a single phase that is stabilized through entropy. However, HEO materials require a complex solid-state reaction process and often exhibit phase segregation and inhomogeneity after processing, which can lead to modifications in properties and stability. Here we explore the phase heterogeneity in (CoCuMgNiZn)O prepared using two different processing routes. Coarse-grain samples were prepared through reaction sintering of unreacted powders using conventional sintering, while fine-grain samples were prepared by sintering pre-synthesized nanopowders using spark plasma sintering. By leveraging these processing routes, we show that it is possible to produce single phase fully dense HEO ceramics with grain sizes spanning several orders of magnitude. Using X-ray diffraction, electron microscopy and atom probe tomography, we confirm that the samples are chemically homogenous across multiple length scales. Critically, no chemical segregation is observed regardless of processing method and grain size. |
Proceedings Inclusion? |
Planned: |
Keywords |
Ceramics, Characterization, Other |