The emergence of ferrous-medium entropy alloys (FeMEAs) with excellent tensile properties represents a potential direction for designing alloys based on metastable engineering. In this study, an FeMEA is successfully fabricated using laser powder bed fusion (LPBF), a metal additive manufacturing technology. Tensile tests are conducted on the LPBF-processed FeMEA at room temperature and cryogenic temperatures (77 K). At 77 K, the LPBF-processed FeMEA exhibits high yield strength and excellent ultimate tensile strength through active deformation-induced martensitic transformation. Furthermore, due to the low stability of the face-centered cubic (FCC) phase of the LPBFprocessed FeMEA based on nano-scale solute heterogeneity, stress-induced martensitic transformation occurs, accompanied by the appearance of a yield point phenomenon during cryogenic tensile deformation. This study elucidates the origin of the yield point phenomenon and deformation behavior of the FeMEA at 77 K.

1. Introduction
2. Experimental
    2.1. Sample fabrication
    2.2. Microstructure analysis and cryogenic tensile test
3. Results and Discussion
    3.1. Initial microstructure
4. Conclusion
Acknowledgement
References

• Seungyeon Lee(Department of 3D Printing Materials, Korea Institute of Materials Science (KIMS), Changwon 51508, Republic of Korea, Department of Metallurgical Engineering, Pukyong National University, Busan 48513, Republic of Korea)
• Kyung Tae Kim(Department of 3D Printing Materials, Korea Institute of Materials Science (KIMS), Changwon 51508, Republic of Korea)
• Ji-Hun Yu(Department of 3D Printing Materials, Korea Institute of Materials Science (KIMS), Changwon 51508, Republic of Korea)
• Hyoung Seop Kim(Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea, Graduate Institute of Ferrous and Energy Materials Technology (GIFT), Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea, Center for Heterogenic Metal Additive Manufacturing, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea)
• Jae Wung Bae(Department of Metallurgical Engineering, Pukyong National University, Busan 48513, Republic of Korea) Corresponding author
• Jeong Min Park(Department of 3D Printing Materials, Korea Institute of Materials Science (KIMS), Changwon 51508, Republic of Korea) Corresponding author