Microstructure and Microsegregation in Directionally Solidified FeCoNiCrAl High Entropy Alloy

Abstract

Directional solidification (DS) of FeCoNiCrAl high entropy alloy is carried out to investigate the microstructures and microsegregation under controlled solidification conditions. With an increasing solidification rate, the interface morphology grows in a planar, cellular and dendritic manner. The microstructures of the dendritic and interdendritic segregation areas are found to be spherical precipitates and basket-weave structures, respectively. With the help of an electron microprobe, microsegregation is determined in directionally solidified FeCoNiCrAl high entropy alloys. In contrast to the as-cast condition, directional solidification can refine microstructures of FeCoNiCrAl high entropy alloy dramatically and reduce microsegregation effectively.