Sunflower-like Solidification Microstructure in a Near-eutectic High-entropy Alloy

Abstract

Considering the inherent advantages of eutectic alloys as high-temperature materials, eutectic high-entropy alloys provide a brand new research direction for developing materials to be used in high-temperature environments. Along this line of thinking, the solidification microstructure in a near-eutectic Al2CrCuFeNi2 alloy was studied. A unique sunflower-like eutectic colony structure was observed, where the Ni–Al-rich B2 phase formed as the primary phase with a spherical or ellipsoidal morphology, the Ni–Al-rich B2/Cr-rich A2 eutectics grew on the primary phase in a radial manner, and the primary B2 phase further decomposed into nearly cubic particles dispersed in the matrix at lower temperatures.