Effect of passivation on anticorrosion property of 0Cr17Ni4Cu4Nb stainless steel in marine atmosphere of Xisha Islands
[Introduction]The corrosion behaviors of unpassivated and passivated 0Cr17Ni4Cu4Nb stainless steels during exposure in the marine atmosphere of Xisha islands for one year were studied.[Method]The corroded surface morphologies of unpassivated and passivated 0Cr17Ni4Cu4Nb stainless steels and the compositions of their corrosion products were examined by using scanning electron microscope(SEM),energy-dispersive spectrometer(EDS),video microscope(VM),and X-ray diffractometer(XRD).[Result]Corrosion occurred mainly in the form of pitting on the surface of 0Cr17Ni4Cu4Nb stainless steel after being exposed in marine atmosphere for a certain period no matter whether it was passivated or not.The relationship between weight loss and exposure time followed the power function.The corrosion product was mainly composed of β-FeOOH.Based on the comparison in the coverage of corrosion product and depth of corrosion pit,it was shown that passivation could improve the corrosion resistance of 0Cr17Ni4Cu4Nb stainless steel,but not provide a long-term protection in the marine atmosphere of Xisha islands.[Conclusion]It is necessary to explore a novel protection technology to improve the corrosion resistance of 0Cr17Ni4Cu4Nb stainless steel for its service in marine atmosphere.
NETL
NSTL
万方数据
