Deformation Behavior and Processing Map of AlCoCrFeNiTi0.5 High-Entropy Alloy at High Temperature

Abstract

AlCoCrFeNiTi0.5 high-entropy alloy (HEA) shows excellent properties in hardness and corrosion resistance. AlCoCrFeNiTi0.5 HEA was prepared using a non-consumable vacuum arc furnace. Hot-deformation behavior of AlCoCrFeNiTi0.5 HEA was explored under 1073–1373 K with a strain rate between 0.001 and 1 s−1 using a Gleeble-3800 thermomechanical simulator. The constitutive equation was established using the Arrhenius model, and the deformation activation energy and material constant were obtained. The processing map of HEA within 0.3–0.6 deformation was drawn according to dynamic material model (DMM). The results show that the hot-deformation process of HEA is dominated by work hardening combined with dynamic recovery, and dynamic recrystallization. The flow stress of HEA is significantly affected by deformation temperature and strain rate. The constitutive equation was constructed and verified, and the correlation coefficient of R2 = 0.9873 indicated that the constitutive equation can be used to accurately predict the flow stress of HEA. The processing map of HEA shows that the optimal hot-working process parameters are in the range of temperature 1150–1300 K and strain rate 0.002–0.05 s−1. This work will provide theoretical guidance for the hot-processing of HEA, which effectively promotes the application of the HEA in industry.