Effects of electropolishing on corrosion and stress corrosion cracking of Alloy 182 in high temperature water

Effects of changes in surface chemical composition and microstructure by electropolishing on corrosion and stress corrosion cracking (SCC) of Alloy 182 in high temperature water were investigated. The results showed that electropolishing mitigated the corrosion, intergranular corrosion and SCC of Alloy 182. This is attributed to formation of the Cr-enriched, protective oxide on electropolished surface due to the enrichment of Cr by electropolishing. In particular, formation of the protective, blunted oxide at grain boundaries on electropolished surface mitigated the intergranular corrosion and caused a lower SCC susceptibility of Alloy 182.