Supplementary file

Achieving high strength and high ductility in Al0.3CoCrNi medium-entropy

alloy through multi-phase hierarchical microstructure

Praveen Sathiyamoorthia,b, Jeong Min Parka,b, Jongun Moona,b, Jae Wung Baea,b, Peyman

Asghari-Rada,b, Alireza Zargaranc, and Hyoung Seop Kimd,*

aDepartment of Material Science and Engineering, Pohang University of Science and

Technology (POSTECH), Pohang 37673, South Korea

bCenter for High Entropy Alloys, Pohang University of Science and Technology (POSTECH),

Pohang 37673, South Korea

cGraduate Institute of Ferrous Technology (GIFT), Pohang University of Science and

Technology (POSTECH), Pohang 37673, South Korea

d Department of Materials Science and Engineering, Yonsei University, Seoul 03722, South

Korea

*Correspondence: hskim@postech.ac.kr; Tel.: +82‐54‐279‐2150

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Figure. S1. EBSD-IPF and KAM maps of sample annealed at 800 oC for 60 min indicating

recrystallized and non-recrystallized regions.

Figure. S1 shows the EBSD-IPF and KAM map of sample annealed at 800 oC for 60 min (MPH

sample). The IPF and KAM clearly indicates that the microstructure consists of recrystallized

fine grains, coarse grains, and non-recrystallized regions.

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Figure. S2. EBSD-IPF and KAM maps of sample annealed at 1200 oC for 60 min indicating

fully recrystallized coarse grain microstructure (average grain size: 80 ± 37).

Figure. S2 shows the EBSD-IPF and KAM map of sample annealed at 1200 oC for 60 min

(SPCG sample). The IPF and KAM clearly indicates that the microstructure consists of only

recrystallized grains with the grain size ranging from ~20 µm to ~200µm.

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Figure. S3. LUR curve of MPBMH and SPCG microstructure for the same stress level

Figure. S3 shows the LUR curve of MPH and SPCG microstructure for the same stress level.

The MPH sample shows wider hysteresis loop than the SPCG sample at the same stress level,

indicating large back stress generated in the MPH structure. The hysteresis loop observed in the

SPCG sample can be attributed to the heterogeneous strain distribution due to the wide range of

grain size.

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