Nitrate on localized corrosion of carbon steel and stainless steel in aqueous solutions

摘要: Abstract Nitrate is significant for corrosion process, which has been extensively studied decades, while some issues remain unclear. Adsorption and reduction mechanisms are widely proposed but separately in literature, results inconsistent regarding different modes conditions. mechanism of nitrate, mostly as competitive adsorption against chloride, discussed electrode potential, concentration, temperature alloy composition. However, it to be based on a premise that nitrate cannot stimulate corrosion, fully interpreted by mechanism. This inadequacy made up mechanism, consuming protons producing water lower aggressiveness. Based these mechanisms, effect localized carbon steel stainless aqueous solutions reviewed details, including pitting, crevice cracking. tends passivate salt-covered pit, not salt-free pit since proton migration across salt layer unavailable. we suggest sufficient may through alone, further work required suggested. Effect relatively consistent, inhibit dissolution chloride. also important cracking, initiated from intergranular steels due imperfect passivation, steels. Competition between cracking can interpret inhibitive/non-inhibitive/promoting nitrate. Corrosion products within local site dissolving discussed, mass transport enhance stability dissolution. generally classified inhibitor described dangerous inhibitor.