| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
|
Hume-Rothery Symposium on Alloy Microstructure Science and Engineering
|
| Presentation Title |
Ordering Induced Phase Stabilities and Transformation Pathways in FCC Based Complex Concentrated Alloys or High Entropy Alloys |
| Author(s) |
Sriswaroop Dasari, Abhishek Sharma, Bharat Gwalani, Stephane Gorsse, Rajarshi Banerjee |
| On-Site Speaker (Planned) |
Rajarshi Banerjee |
| Abstract Scope |
Adding elements such as Al or Ti to near random face-centered cubic (FCC) solid solutions, such as CoFeNi or CoCrFeNi, introduces strong ordering tendencies in high entropy alloys (HEAs) or complex concentrated alloys (CCAs). This presentation will demonstrate the strong influence of Al addition to equiatomic CoFeNi on the stability and metastability of ordered phases (e.g. L12 and B2), and the consequent phase transformation pathways. A case study will be presented from a model Al0.3CoFeNi HEA/CCA wherein the phase stability (and attendant metastability) can lead to many different microstructures, including a homogeneous distribution of nanometer scale L12 (gamma prime-like) precipitates within the FCC matrix, ordered B2 precipitates distributed within the FCC matrix, a combination of L12 and B2 precipitates, and a complex four-phase hierarchical nano-lamellar microstructure consisting of alternating lamellae of FCC + L12 and B2 + BCC within eutectoid-like colonies. The underlying thermodynamic and kinetic factors will be discussed. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Entropy Alloys, Phase Transformations, Characterization |