Synthesis and Electrochemical Corrosion Behaviour of High Entropy Alloys

High entropy alloys (HEAs) are alloys based on a minimum of five principal elements, which can also have some minor elements for improving the properties according to the applications. The present study deals with the minor elements (Al and Mn) containing CoCrFeNiTi-based HEAs and discusses the effect of Ti on the corrosion behaviour of the HEAs. The HEAs were synthesized in an inert atmosphere using a vacuum arc melting furnace. The as-synthesized HEA samples were characterized for microstructure, phases, hardness, and density. The hardness and density were influenced by changing the amount of Ti in HEAs. The electrochemical corrosion behaviour was analysed using a potentiostat in 3.5% NaCl and 0.1M H2SO4 solutions. The corrosion results suggest that the high Ti-containing HEAs show better corrosion resistance in the NaCl and H2SO4 solutions due to the formation of TiO2 on the sample surface.