Plastic Deformation Behavior of 40Fe-25Ni-15Cr-10Co-10V High-Entropy Alloy for Cryogenic Applications

A single FCC phase 40Fe-25Ni-15Cr-10Co-10V high-entropy alloy was designed, fabricated, and evaluated for potential cryogenic applications. The alloy forms a single FCC phase and exhibits higher yield strength, tensile strength, and elongation at cryogenic temperature (77K) than at room temperature (298K). The superior tensile properties at cryogenic temperature are discussed based on the formation of deformation twins during the tensile test at cryogenic temperature. In addition, a constitutive model reflecting the cryogenic deformation mechanism (i.e., twinning-induced plasticity) was implemented into the finite element method to analyze this behavior. Experimental results and the finite element analysis suggest that the increase in plastic deformation capacity at cryogenic temperature contributes to the formation of deformation twins.