| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Chemistry and Physics of Interfaces
|
| Presentation Title |
Direct Atomic-Scale Observations of Grain Boundary Phase and Segregation Transitions |
| Author(s) |
Christian Liebscher |
| On-Site Speaker (Planned) |
Christian Liebscher |
| Abstract Scope |
We show that grain boundary (GB) phases exist in elemental copper. Atomic resolution scanning transmission electron microscopy resolves two distinct GB phases termed “pearl” and “domino” that are coexisting in the same GB. By in situ heating experiments it is even possible to directly monitor such transformations at 300ºC. The experiments indicate that the GB phase junctions plays an important role in the transformation kinetics and GB phase coexistence.
In the reminder of the talk, we demonstrate novel icosahedral states induced at tilt GBs in titanium upon iron segregation. Our atomic resolution observations reveal that these icosahedral cage structures exist at different symmetric and asymmetric GBs in the form of isolated cages and cage clusters. In combination with advanced atomistic modelling, we explore the underlying structure of the icosahedral building blocks of the GB phases and discuss their unique topological properties. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Thin Films and Interfaces, Phase Transformations, Titanium |