| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Transformations and Microstructural Evolution
|
| Presentation Title |
Novel lightweight CoCrNiAlSi medium-entropy alloys with high strength and ductility |
| Author(s) |
Pei-Yu Chen, Jhen-Yu Yen, Chun-Hway Hsueh |
| On-Site Speaker (Planned) |
Pei-Yu Chen |
| Abstract Scope |
The purpose of this study is to mitigate the strength-ductility trade-off in CoCrNi medium entropy alloys (MEAs) via Al (for strength enhancement) and Si (for stacking fault energy reduction) co-doping. The co-doping effects on the microstructures, deformation mechanisms, stacking fault energy and mechanical properties of CoCrNi MEAs are discussed. CoCrNi and three (CoCrNi)97-xAlxSi3 (x=3, 5, 7) MEAs were fabricated using arc melting, followed by homogenization, cold rolling and annealing. As the Al doping increased, CoCrNiAlSi MEAs resulted in a significant increase in strength while maintaining good ductility due to the co-precipitation of B2 and σ phases. Compared to CoCrNi MEA with the tensile strength of 878.5 MPa and fracture strain of 62.9%, (CoCrNi)92Al5Si3 MEA exhibited a good combination of tensile strength (1.2 GPa) and ductility (48.5%). Moreover, the alloy's density was ~10% lower than that of CoCrNi, suggesting the great potential of the alloy for structural applications. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, |