| Title |
Microstructure and Mechanical Properties of CrMnFeCoNi High-Entropy Alloys Produced by Warm
Multi-Pass Caliber Rolling |
| Authors |
최지환(Jihwan Choi) ; 정휘윤(Hwi Yun Jeong) ; 임진수랑(Jinsurang Lim) ; 이욱진(Wookjin Lee) ; 이제인(Je In Lee) |
| DOI |
https://doi.org/10.3365/KJMM.2025.63.12.937 |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
High-entropy alloys; Mechanical properties; Microstructure; Shape memory alloys; Stress-induced martensitic transformation Thermomechanical processing |
| Abstract |
Designing novel high-entropy alloys (HEAs) with low stacking fault energy has been drawn
significant attention for achieving a unique combination of high strength and ductility via transformationinduced
plasticity (TRIP) mechanism. However, extensive work hardening of TRIP HEAs have led to the
difficulties in metalworking, which required very high thermomechanical processing temperature even to
1000 oC. In this study, we introduced warm multi-pass caliber rolling to Cr20Mn20Fe20Co20Ni20 (Ni20) HEA and
Cr20Mn20Fe20Co35Ni5 (Ni5) TRIP HEA to validate the feasibility of thermomechanical processing for TRIP
HEAs at 400 oC. Grain growth behavior of annealed HEA bars was analyzed after recrystallization and
Vickers hardness test was performed to compare the Hall-Petch relationship for Ni5 and Ni20 HEAs. Ni5
TRIP HEA exhibited higher strain hardening but lower tensile elongation than Ni20 HEA, which was
responsible for the poor workability of Ni5 TRIP HEA at room temperature. Tensile tests in temperature
range from -180 to 225 oC revealed that Ni5 TRIP HEA showed stress-induced martensitic transformation
that had preceded slip deformation of the austenitic phase in 10 ? 100 °C, which is the temperature range
feasible for shape memory applications. These results demonstrate that the warm multi-pass caliber rolling
can be an effective process to fabricate TRIP HEA billets for structural and functional applications. |