In this study, the layered structures of immiscible Fe and Cu metals were employed to investigate the interface evolution through solid-state mixing. The pure Fe and Cu powders were cold-consolidated by high-pressure torsion (HPT) to fabricate a layered Cu-Fe-Cu structure. The microstructural evolutions and flow of immiscible Fe and Cu metals were investigated following different iterations of HPT processing. The results indicate that the HPTprocessed sample following four iterations showed a sharp chemical boundary between the Fe and Cu layers. In addition, the Cu powders exhibited perfect consolidation through HPT processing. However, the Fe layer contained many microcracks. After 20 iterations of HPT, the shear strain generated by HPT produced interface instability, which caused the initial layered structure to disappear.

Abstract
1. Introduction
2. Experimental methods and procedure
3. Results and Discussion
4. Conclusion
References

• Peyman Asghari-Rad(Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH)/Center for High Entropy Alloys, Pohang University of Science and Technology (POSTECH))
• Yeon Taek Choi(Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH))
• Nhung Thi-Cam Nguyen(Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH)/Center for High Entropy Alloys, Pohang University of Science and Technology (POSTECH))
• Praveen Sathiyamoorthi(Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH)/Center for High Entropy Alloys, Pohang University of Science and Technology (POSTECH))
• Hyoung Seop Kim(Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH)/Center for High Entropy Alloys, Pohang University of Science and Technology (POSTECH)/Graduate Institute of Ferrous Technology (GIFT), Pohang University of Science and Technology (POSTECH)/Institute for Materials Research, Tohoku University) Corresponding Author