Effect of Zr Addition on Microstructure and Properties of FeCrNiMnCoZr x and Al0.5FeCrNiMnCoZr x High Entropy Alloys

Abstract

In this study, the effect of Zr addition on phase formation, microstructure, and hardness of FeCrNiMnCoZr x and Al0.5FeCrNiMnCoZr x were investigated. High entropy alloys (HEA) were synthesized using arc melting technique in argon (Ar) atmosphere (x = 0, 0.1, 0.2, 0.3). Ingots were homogenized for 24 h at 900 °C in Ar atmosphere. Phase formation, microstructure and hardness of HEAs were investigated using field emission scanning electron microscope, X-ray diffraction and Vickers microhardness tester. Electron micrographs of HEAs showed majorly dendritic(DR) and interdendritic(ID) phases. For both FeCrNiMnCoZr x and Al0.5FeCrNiMnCoZr x alloys, amount of ID phases is seen to increase with increased Zr content. Aluminium containing HEAs showed fine needle-shaped precipitates dispersed throughout the matrix phase. XRD results confirmed the presence of mixed FCC/BCC phases in FeCrNiMnCoZr x alloys and BCC as majority phase in Al0.5FeCrNiMnCoZr x alloys. As the Zr content increased, hardness of HEA increased.