Near-equiatomic high-entropy decagonal quasicrystal in Al20Si20Mn20Fe20Ga20

Abstract

High-entropy alloys (HEAs) contain multiple principal alloying elements, but usually with simple crystal structures. Quasicrystals are structurally complex phases, but are generally dominated by only one element. However, nearequiatomic high-entropy quasicrystals have rarely been reported because they are difficult to prepare experimentally and predict theoretically. Therefore, the preparation and crystal structures of near-equiatomic high-entropy quasicrystals have drawn much interest. We report a quinary decagonal quasicrystal (DQC) with near-equiatomic alloying elements in Al20Si20Mn20Fe20Ga20 melt-spun ribbons, which is the first to our knowledge. Meanwhile, the structural features of the DQC are characterized in detail. The configurational entropy of both the alloy and DQC satisfies the entropy-based criterion for HEAs, suggesting a high-entropy DQC. Our findings provide a new strategy to develop high-entropy quasicrystals.