FCC계 고엔트로피 합금의 냉간 인발 유한요소해석 및 실험적 검증

We present a multi-step cold drawing for a non-equiatomic Co10Cr15Fe25Mn10Ni30V10 high entropy alloy (HEA) with a simple face-centered cubic (FCC) crystal structure. The distribution of strain in the cold-drawn Co10Cr15Fe25Mn10Ni30V10 HEA wires was analyzed by the finite element method (FEM). The effective strain was expected to be higher as it was closer to the surface of the wire. However, the reverse shear strain acted to cause a transition in the shear strain behavior. The critical effective strain at which the shear strain transition behavior is completely shifted was predicted to be 4.75. Severely cold-drawn Co10Cr15Fe25Mn10Ni30V10 HEA wires up to 96% of the maximum cross-sectional reduction ratio were successfully manufactured without breakage. With the assistance of electron back-scattering diffraction and transmission electron microscope analyses, the abundant deformation twins were found in the region of high effective strain, which is a major strengthening mechanism for the cold-drawn Co10Cr15Fe25Mn10Ni30V10 HEA wire.