Research progress in hot deformation behavior of high entropy alloys

Abstract

The high entropy alloy overturns the traditional design idea that one or two elements are the main elements, and its design concept of multi-element and high mixing entropy endows it with excellent properties such as high strength, high toughness, corrosion resistance, high temperature resistance and oxidation resistance, etc., making high entropy alloy being a research hotspot in the field of new high-performance structural materials. The research and development of high entropy alloys will inevitably lead to engineering application, where hot working is an important way to further control the microstructure and properties. As a result, the hot deformation behavior which characterizes the hot working properties has become a new research emphasis and hotspot. Based on the research status of hot deformation, the high entropy alloys were classified according to phase structure firstly, and the constitutive relation of hot deformation and prediction model of flow stress were introduced. Then, microstructure evolution of high entropy alloys with FCC, FCC+BCC and BCC structures during hot deformation was analyzed. On this basis, deformation mechanism and recrystallization mechanism during hot deformation were summarized. Finally, the challenges faced by hot deformation of high entropy alloys in the future are emphasized, and some suggestions for research trends in the future are put forward as follows: establishing constitutive relation based on physical properties of high entropy alloys, constructing recrystallization model based on structural characteristics of high entropy alloy, strengthening systematic study of hot deformation behavior under different preparation conditions and complex loads, and breaking through the key preparation process of high entropy alloy.

Keywords

• high entropy alloy
• hot deformation
• constitutive relation
• microstructure evolution
• deformation mechanism
• recrystallization mechanism