| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advances in Bcc-Superalloys
|
| Presentation Title |
Evolution of the BCC + B2 microstructure and its high temperature stability in refractory high entropy alloys (INVITED TALK) |
| Author(s) |
Vishal Soni, Abhishek Sharma, Sriswaroop Dasari, Zachary Kloenne, Jean-Philippe Couzinie, Oleg N. Senkov, Daniel B. Miracle, Srinivasan G. Srivilliputhur, Hamish Fraser, Rajarshi Banerjee |
| On-Site Speaker (Planned) |
Rajarshi Banerjee |
| Abstract Scope |
Recent results indicate that in refractory high entropy alloys (RHEAs) involving a mixture of BCC and B2 phases, the alloy initially decomposes into a microstructure comprising a continuous ordered B2 matrix with discrete cuboidal BCC pockets, resembling a superalloy-like microstructure. Further, in some cases isothermal annealing at 600°C-800°C results in a phase inversion into a continuous BCC matrix with discrete B2 precipitates. However, these B2 precipitates appear to be a metastable transition phase, eventually transforming into an hP18 ordered phase. This hP18 phase is an ordered omega type structure, resulting from a displacive shuffle of the {111} type planes of the parent B2 accompanied by diffusional reordering on these planes. The compositional and structural changes associated with this transformation, has been characterized using detailed TEM and APT based techniques. Investigating this B2 to hP18 transformation is critical for understanding phase stability of B2 at high temperatures, impacting high temperature applications. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Entropy Alloys, High-Temperature Materials, Characterization |