Strengthening of Fe ₅₀ Mn ₂₅ Ni ₁₀ Cr ₁₅ Medium‐Entropy Alloys by Mo Addition for Cryogenic Applications

The effect of Mo addition of Fe 50 Mn 25 Ni 10 Cr 15 medium‐entropy alloy (MEA) on its cryogenic mechanical properties is investigated. It is found that the optimized (Fe 50 Mn 25 Ni 10 Cr 15 ) 99.5 Mo 0.5 MEA exposes the yield strength, tensile strength, and ductility of 690 MPa, 1148 MPa, and 63% at 77 K, respectively. Especially, the yield strength increases by 29% after Mo addition. Herein, the solid‐solution strengthening, twinning‐induced plasticity, and transformation‐induced plasticity are beneficial to reveal the high work hardening capability and good strength‐ductility synergy at 77 K. This research can offer guidance for the design of low‐cost and high‐performance MEAs for cryogenic applications.