Abstract
In present study, a Co-Cr-Fe-Ni-Ti high-entropy alloy has been cast into single crystal by a directional solidification process. A seed material of Rene' 142 has been used during the casting process. The aim of present study is to understand the solidification and phase stability of this high entropy alloy. The as-cast and heat treated microstructures have been observed by SEM; with proper heat treatment, this material is shown to possess a FCC structure, and its high Ti content can promote the formation of η phase, which exists in interdendritic region. EPMA has been performed to study the segregation behavior. High temperature thermal exposures have been conducted to investigate the microstructural stability. DTA has been carried out to examine the phases and related thermal properties of the alloys. The multi-principal-element effects are to be discussed with results from those analyses.