| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Transformations and Microstructural Evolution
|
| Presentation Title |
Study of Deformation Mechanism and Microstructural Evolution in a Dual-Precipitation Strengthened Novel CoCrNi Medium Entropy Alloy by Al and Nd Co-Doping |
| Author(s) |
Chung Chih Tsai, Chun-Hway Hsueh |
| On-Site Speaker (Planned) |
Chung Chih Tsai |
| Abstract Scope |
In this study, the deformation mechanism at the nanoscale of CoCrNi medium entropy alloy (MEA) during uniaxial tension at various temperatures was investigated. To achieve this, a series of (CoCrNi)92.5–x–yAlxNdy MEAs was fabricated by vacuum arc melting, homogenization, hot-rolling and annealing. With co-doping of Al and Nd in CoCrNi, B2 NiAl and HCP NdNi5 precipitates formed in the FCC CoCrNi matrix, resulting in the improved strength and hardness of the alloy. The obtained stress–strain curves were discussed based on precipitate hardening, dislocation structure evolution, stacking fault energy, and twinning/detwinning occurrence. Also, a systematic investigation of the cryogenic tensile properties of (CoCrNi)92.5–x–yAlxNdy MEAs is reported in this work. Compared to other CoCrNi-based MEAs, both the yield strength and ultimate tensile strength in this work were enhanced significantly while the fracture strain remained at 37%, which was mainly attributed to grain refinement and precipitation strengthening. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Entropy Alloys, Mechanical Properties, Characterization |