| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Transformations and Microstructural Evolution
|
| Presentation Title |
Predictably Tuning Transformation Temperatures in Thin Epitaxial Films |
| Author(s) |
Ashley N. Bucsek, Ananya Renuka Balakrishna, Abhinav Prakash, Bharat Jalan, Richard James |
| On-Site Speaker (Planned) |
Ashley N. Bucsek |
| Abstract Scope |
For the majority of functional material applications involving phase transformations, it is necessary to tune the transformation temperature for the specific operating conditions of the application. Here, we focus on the ability to tune the transformation temperature using stress. Because the magnitudes of the biaxial stress states in epitaxially grown films can be relatively large (1–2%) while also resisting the formation of dislocations, we focus on thin epitaxial films where the change in transformation temperature can be quite dramatic. For example, we have observed a transformation temperature depression of roughly 1000°C, bringing a normally inaccessible phase transformation to room temperature. Here, we present a free energy approach to predicting transformation temperatures in thin epitaxial films. This approach builds on theory describing compatibility requirements in thin films versus bulk materials. The result is a straightforward approach for engineering phase-transforming films with desired transformation temperatures. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |