| About this Abstract |
| Meeting |
2021 TMS Annual Meeting & Exhibition
|
| Symposium
|
High Entropy Alloys IX: Alloy Development and Properties
|
| Presentation Title |
FCC-HCP Transformation in Cr-Mn-Fe-Co-Ni High Entropy Alloys:- Mechanical Property and Nanograin Formation |
| Author(s) |
Koichi Tsuchiya, Jangho Yi, Baozhen Jiang, Je In Lee |
| On-Site Speaker (Planned) |
Koichi Tsuchiya |
| Abstract Scope |
A series of high-entropy alloys with different FCC/HCP phase stability was designed. Ingots of Cr20Mn20Fe20Co40-xNix (x=0~20) were prepared by HF melting and rolled into the bar. They are heat treated at 1473 K for 48 hrs followed by water quench. Samples with 0~5mol%Ni are composed of HCP and FCC phases after the heat treatment, while others are in the FCC single phase state. For the 15~20Ni alloys, HPT led to a drastic increase in micro-Vickers Hardness (Hv). This can be attributed to the rapid progress of grain refinement. BSD-SEM observations revealed that pronounced formation of lamellar structures of about 100 nm width separated by nanotwins. They accelerate an increase in dislocation density and led to the formation of equiaxed nanograins (~50 nm) by continuous dynamic recrystallization. Meanwhile, hardness increase was less significant for the lower Ni content alloys with higher HCP stability. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Entropy Alloys, Phase Transformations, Mechanical Properties |