Electrochemical corrosion and high temperature hot corrosion behavior of NbTaTiV and CrNbTaTiV high entropy alloy

Abstract

NbTaTiV and CrNbTaTiV were fabricated by arc melting and effect of Cr element on electrochemical and high temperature hot corrosion behavior were compared. Electrochemical corrosion investigations revealed that Laves phase at grain boundaries of CrNbTaTiV would underwent galvanic corrosion, resulting in a marginal reduction in corrosion resistance. The results of high temperature hot corrosion showed that within Na2SO4 + 25 wt% NaCl molten salt environment, the oxide film formed by Cr element effectively improved the surface stability, reduced the formation of unprotected loose corrosion products and the generation of low melting point chlorides with strong volatility, which improved the resistance of molten salt corrosion.