Recent progress in lightweight high-entropy alloys

High-entropy alloys (HEAs) have attracted extensive attention due to their novel compositional design and excellent properties, and the concept of "entropy regulation" has been widely used to develop new performance-oriented alloys. Lightweight high-entropy alloys (LHEAs) are a kind of important lightweight materials under the guidance of "entropy regulation". They exhibit a series of special properties related to the high alloying elements and high mixing entropy, including high specific strength, high specific hardness, excellent corrosion resistance. These advantages make LHEAs great application potential in the lightweight material fields. However, there are still many questions to be solved. For example, phase formation rules of LHEAs are still ambiguous, and comprehensive performance under specific service environment needs further consideration. Therefore, this paper reviews the composition design, phase formation rules, mechanical properties, physical properties, and chemical properties of some typical LHEAs, and points out the problems it faces and the direction of future development.