About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Transformations and Microstructural Evolution
|
| Presentation Title |
Influence of Cr/Ni Ratio on Phase Stability and σ-phase Precipitation Kinetics in CrMnFeCoNi High-entropy Alloys |
| Author(s) |
Guillaume Laplanche |
| On-Site Speaker (Planned) |
Guillaume Laplanche |
| Abstract Scope |
The equiatomic CrMnFeCoNi high-entropy alloy (HEA) was initially believed to form a stable FCC solid solution because it solidifies in this state and remains so, after forming and recrystallization. Further works have however demonstrated that this alloy decomposes when annealed below ~800°C. In the present work, we show that an increase of the Cr/Ni ratio of the alloy stabilizes the topologically close-packed σ-phase and accelerates its precipitation kinetics, which is also enhanced by a decrease in mean grain size. By analyzing the temporal evolutions of the concentration profiles forming at FCC/σ interfaces and the dimensions of σ-phase precipitates, the diffusion processes responsible for the precipitation kinetics were identified. As the σ-phase is known to cause embrittlement in other alloy systems, its influence on tensile behavior was investigated. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Entropy Alloys, Characterization, Phase Transformations |