Corrosion Resistance of CoCrFeMnNi High Entropy Alloy Compared with 2205 Duplex Stainless Steel in a Simulated Concrete Pore Solution

The comparison of corrosion resistance between CoCrFeMnNi high entropy alloy (HEA) and 2205 duplex stainless steel (DSS) in a simulated concrete pore solution was investigated. The results reveal that compared with 2205 DSS, the passive film produced on CoCrFeMnNi HEA possesses a stronger protective ability with a thicker and more stable structure. The initiation frequency, lifetime and peak current value of metastable pitting of the HEA are lower than those of 2205 DSS, indicating that the metastable pitting corrosion is more difficult to occur in HEA. Moreover, the HEA suffers from scattered small-sized pitting, whereas dense and large pits are generated on 2205 DSS. Thus, the HEA exhibits a superior corrosion resistance in comparison with the DSS.