| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Transformations and Microstructural Evolution
|
| Presentation Title |
Characterizing the Impact of Precipitation-Induced Strain Fields on Phase Transformation in High Temperature NiTiHf-based Shape Memory Alloys |
| Author(s) |
Eitan Hershkovitz, Flávia da Cruz Gallo, Matthew Jones, Timothy Yoo, Michele V. Manuel, Honggyu Kim |
| On-Site Speaker (Planned) |
Eitan Hershkovitz |
| Abstract Scope |
Shape memory alloys (SMAs) are a class of metallic materials that can recover their pre-defined shape, upon heating, after deformation. Conventional SMAs are limited to low service temperatures due to low martensitic transformation (MT) temperatures and structural/cyclic instability. Incorporation of coherent nanoscale precipitates has been demonstrated to improve mechanical properties and increase the MT temperatures, thus enabling the application of SMAs in high-temperature service conditions. Computational research has shown that strain fields at the matrix/precipitate interface play an important role in controlling the MT behavior. However, there is a lack of experimental measurements of these strain fields. In this work, we map the strain fields around coherent precipitates in NiTiHf-based SMAs with high spatial resolution, and quantify their impact on the MT. Specifically, we utilize scanning electron nanobeam diffraction and in-situ heating experiments in electron microscopy to measure the strain fields in NiTiHf-based SMAs across varying compositions and heat treatments. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Characterization, High-Temperature Materials, Phase Transformations |