About this Abstract |
Meeting |
MS&T23: Materials Science & Technology
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Symposium
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High Entropy Materials: Concentrated Solid Solutions, Intermetallics, Ceramics, Functional Materials and Beyond IV
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Presentation Title |
Dislocation-mediated Plasticity in Entropy Stabilized Oxides at Room Temperature |
Author(s) |
Xin Wang, Justin Cortez, Alexander D. Dupuy, Julie M. Schoenung, William Bowman |
On-Site Speaker (Planned) |
William Bowman |
Abstract Scope |
Dislocations are common in metallic materials, but their importance has not been fully recognized in ceramics. Entropy stabilized oxides (ESOs), a new family of ceramics, have garnered considerable attention in recent years owing to their compositional complexity and emerging functionalities. Here [1], we report dislocation-mediated plastic deformation in rocksalt (Co,Cu,Mg,Ni,Zn)O at room temperature. ESOs with distinct grain sizes were synthesized and deformed by nanoscratch tests. The deformation microstructures were characterized using scanning/ transmission electron microscopy (S/TEM). We show that the dislocation density in ESO with micron-sized grains after deformation at room temperature can reach 1014 m-2, which is comparable with that in cold-worked alloys. In contrast, nanocrystalline ESO exhibit evidence for grain boundary sliding and intergranular crack propagation, in addition of dislocation slip, indicating that the mechanical behavior of ESOs can be tailored through microstructure.
[1] X. Wang…W.J. Bowman (2023) Materials Research Letters |