Microstructural evolution and tensile property enhancement of low-cost Fe-24Mn-22Ni-12Cr medium-entropy alloy by cryogenic caliber rolling

Abstract

High- and medium-entropy alloys (HEAs/MEAs) have been extensively developed over the last two decades owing to their superior mechanical performances from cryogenic to high temperatures. However, the high raw material costs of recently developed HEAs/MEAs limit their practical applications. In this study, we designed cost-effective Co-free, Fe-based MEAs based on thermodynamic calculations. To enhance the yield strength of the MEA, multi-pass caliber rolling, which has been recognized for improving the yield strength, was implemented at room and cryogenic temperatures. The yield strengths substantially improved from 229 MPa for the annealed specimen to 862 MPa for the sample caliber-rolled at cryogenic temperatures while maintaining good ductility. Based on the above findings, the effects of multi-pass caliber rolling at cryogenic temperatures on the microstructural evolution, mechanical properties, and deformation behavior are discussed.