About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advances in Ceramic Materials and Processing
|
| Presentation Title |
Toward Deformable Ordered Ceramics: Dislocation Mobility in Th₆Mn₂₃-Type Structures |
| Author(s) |
Julia T. Purstl, Rob P. Thompson, Lilian Vogl, Peter Schweizer, Thomas E.J. Edwards, Amit Sharma, Alexander Groetsch, Johann Michler, Nicholas G. Jones, William J. Clegg |
| On-Site Speaker (Planned) |
Julia T. Purstl |
| Abstract Scope |
Ceramics and intermetallics often exhibit high Peierls stresses (>1 GPa) due to their intrinsic ordering, limiting dislocation mobility and thus fracture resistance. We demonstrate that sustained dislocation motion can be enabled in Th₆Mn₂₃-type intermetallics, whose atomic arrangements resemble the layered structure of MAX phases and other ceramic systems.
Using nanoindentation, TEM, and DFT, we investigate four chemically distinct compounds—Al₁₆Ni₇Ti₆, Al₁₆Co₇Ti₆, Al₁₆Ni₇Zr₆, and Co₁₆Zr₇Si₆—and show that their plastic response is controlled by intrinsic chemical layering parallel to the {111} glide planes. In particular, we find that layer chemistry gives rise to variations in glide resistance, offering a route to compositionally tuned dislocation mobility. The cubic symmetry further facilitates multiaxial glide, enabling bulk plasticity.
Our findings suggest a broader design principle based on chemical layering as a mechanism to engineer plasticity in ordered, brittle materials and open pathways to develop compositionally complex structural ceramics with enhanced deformability for extreme environments. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Ceramics, High-Temperature Materials, Mechanical Properties |