A review on improving mechanical properties of high entropy alloy: interstitial atom doping

High entropy alloy breaks through the traditional concept of alloy design and provides a new way of thinking for alloy composition design. High entropy alloys (HEAs) generally contain five or more alloy elements. According to the requirements of alloy properties, the crystal microstructure and phase composition of alloys can be changed by selectively adding some interstitial atom and controlling the proportion of alloy elements, so as to achieve a breakthrough in alloy properties. This paper introduces the microstructure and core effect of HEAs, analyzes the influence of interstitial atoms C, N, O, B on the phase structure of HEAs, summarizes the influence of solid solution strengthening, grain refinement, and second phase strengthening produced by interstitial atoms on the microstructure and properties of HEAs, and compares the performance strengthening of different interstitial atoms on HEAs, finally, the research focus of the microstructure design of high strength, high toughness and HEAs containing interstitial atoms is proposed.