Dynamic Recrystallization/Recovery of FCC and B2 Phases in a Ni₃₆Fe₃₆Cr₁₀Al₁₇Mo₁ Eutectic High Entropy Alloy

Abstract: Eutectic high entropy alloys (EHEAs) with good casting properties and comprehensive mechanical properties have been widely studied. As an effective way for massive fabrication, hot processing of the EHEAs should be considered, where the microstructure and mechanical properties could also be tailored. In this work, the flow behavior of Ni₃₆Fe₃₆Cr₁₀Al₁₇Mo₁ EHEA, which consists of FCC and B2 phases, were investigated during hot compression at temperatures ranging from 900 to 1180 ℃ and strain rates ranging from 0.05 to 5 s⁻¹. The microstructure evolution as well as the softening mechanism under different deformation conditions were revealed. The dynamic softening processes of the FCC and B2 phases were promoted under high temperature of 1180 ℃. Moreover, the microstructure and dynamic recrystallization/recovery of FCC phase and B2 phase were significantly related to the strain rates. Two different softening mechanisms were observed in the FCC phase with low stacking fault energy. Compared with the FCC phase, the B2 phase with high stacking fault energy had a faster dynamic recovery (DRV) rate with the continuous dynamic recrystallization (CDRX) at all strain rates.