Electrochemical Corrosion of 304 Austenitic Stainless Steel in Nitric Acid Solutions

The effect of nitric acid solutions with different kinds of chemical constituents on the electrochemical corrosion of 304 austenitic stainless steel was investigated. The study was carried out using potentiodynamic cyclic polarization measurements. Electrochemical measurements indicate that nitrate in nitric acid solution impairs the electrochemical corrosion of 304 austenitic stainless steel, while oxalic acid substantially promotes the electrochemical corrosion of 304 stainless steel. The results also show that after adding 1 g/L citric acid, the corrosion current increases from 6.02 μA/cm² to 22.8 μA/cm², indicating an apparent promotion of electrochemical corrosion.