Effect of Cr on the Characteristic of Rust Layer Formed on Low Alloy Steels Immersed in Flowing 3.5%NaCl Solution

Abstract

Abstract The role of Cr concentrated inrust layer formed on Cr-containing steels was investigated. Corrosion products formed on these steels were analyzed by usingXPS, XRD,TEM, and Raman spectroscopy. The result indicates that amorphous Cr(OH)3 and (FeCr)3O4 formed on the Cr-containing steelsresulted in the formation of ultrafine corrosion-product particles and, consequently, a compact rust layer with low electronic conductivity. The Cr-containing rust layer servedmainly to inhibit the cathodic reaction of O2reduction, therebyimproving the flow-accelerated corrosionresistance of the low alloy steel.