fig4

Figure 4. Heterogeneous martensite phase transformation in the HS-HEA at 10% strain. (A) IPF map; (B) Phase map overlayed with IQ map; (C) ECC image; (D and E) Zoom-in ECC images of the marked zone in (C); (F) High-resolution TEM image showing the atomic structure of FCC and HCP phases. EBSD maps and the corresponding ECC image indicate the martensite phase transformation from FCC to HCP occurs in the non-recrystallized zone, forming the lamellar plates, whereas dislocation slip dominates in the recrystallized zone. This suggests heterogeneous deformation behavior in our HS-HEA. The deformation-induced HCP phase obeys the S-N orientation relationship with the FCC matrix. HS: Heterogeneous structure; HEA: high-entropy alloy; IPF: inverse pole figure; IQ: image quality; ECC: electron channeling contrast; TEM: transmission electron microscopy; FCC: face-centered cubic; HCP: hexagonal close-packed; EBSD: electron backscatter diffraction.