About this Abstract |
| Meeting |
2027 TMS Annual Meeting & Exhibition
|
| Symposium
|
Photomechanical and Electromechanical Effects in Structural and Functional Materials
|
| Presentation Title |
Defect chemistry and electric field affect dislocation plasticity across the length scale in functional oxides |
| Author(s) |
Xufei Fang, Chukwudalu Okafor, Atsutomo Nakamura, Oliver Preuss |
| On-Site Speaker (Planned) |
Xufei Fang |
| Abstract Scope |
Defect chemistry for point defect engineering is widely used for tuning the functional properties of oxide ceramics. Most recently, dislocations in ceramics gain renewed research momentum, providing a new perspective for (re)thinking the engineering of functional ceramics. A fundamental understanding of (charged) point defect-dislocation interactions in functional oxides remains largely unexplored. Here, we adopt a scale-bridging deformation approach including nanoindentation, Brinell indentation, and uniaxial bulk compression to investigate the impact of oxygen vacancies and donor-/acceptor doping on the room-temperature dislocation plasticity in model perovskite oxide SrTiO3. Then we couple mechanical deformation with electric field, which also plays an important role in regulating the charges of the defects, hence the dislocation plasticity, particularly at small length scale. We find that oxygen vacancies play a dual role in facilitating dislocation nucleation while suppressing dislocation motion. These insights reveal the importance of defect chemistry and electric field on dislocation plasticity in functional oxides. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Mechanical Properties, Ceramics, Characterization |