An investigation on the corrosion performance of Fe2CoCrNi0.5 based high entropy alloys

The electrochemical and hot corrosion behaviors of Fe 2 CoCrNi 0.5 based HEAs were investigated. The HEA with the best electrochemical corrosion resistance was Fe 2 CoCrNi 0.5 Si 0.25 Cu 0.25 with E corr of − 0.584 V, I corr of 1.47 × 10–4 A/cm 2 . Fe 2 CoCrNi 0.5 Cu 0.25 had the worst resistance to hot corrosion, as caused by the more severe attack and poor adherence of scale. However, Si addition contributed to better corrosion resistance.The positive effect of Si is thought to be associated with rendering the formation of a relatively denser and more adherent scale that could behave as a barrier to the penetration of oxygen and molten salt towards the substrate. • A study to improve corrosion performance of the high entropy alloys is presented. • Enhanced hot corrosion resistance was achieved by adding Si. • Cu addition presented a corrosion scale that was cracked, porous, and non-protective. • The alloying process could be a promising direction in designing corrosion-resistant HEAs.