About this Abstract |
Meeting |
MS&T22: Materials Science & Technology
|
Symposium
|
Manufacturing and Processing of Advanced Ceramic Materials
|
Presentation Title |
Role of Processing and Microstructure on the Phase Transformation in High Entropy Oxides |
Author(s) |
Alexander D. Dupuy, 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. A unique characteristic of HEO materials is their reversible entropy-driven phase transformation, presenting an opportunity to produce oxide materials with highly controlled phase states. Here we explore the impact of grain size on the entropic phase transition in (CoCuMgNiZn)O ceramics. Powders are prepared using solid-state methods, followed by consolidation using free sintering and spark plasma sintering (SPS). By leveraging these processing routes, we show that it is possible to produce fully dense HEO ceramics with grain sizes spanning several orders of magnitude. It is revealed that the grain size significantly influences the morphology of the secondary phase. At large grain sizes the secondary phase manifests in elongated needle morphologies. Conversely, smaller grain sizes confine the size of the secondary phases, leading to a transition in morphology and behavior. |