Influence of electrolyte composition on the corrosion character of 12Cr17 steel in molten alkali metal carbonates

 E.V. Nikitina

ABSTRACT:

Previously, the corrosion of 12Cr17 steel in molten alkali metal carbonates containing different chemical additions was investigated by potentiostatic anodic polarization method. The surface morphology of 12Cr17 steel was studied by X-ray analysis. The mechanism of local corrosion damages was influenced by injecting the corrosion passivators and corrosion activators. Corrosion of the investigated alloy proceeds according to electrochemical mechanism. Steel oxidants were both  dissolved in the melt and carbonate anions. The method of corrosion medium processing (treatment) could be used to protect metal structures from corrosion in high-temperature salt bathes. Combined introduction in salt phase of corrosion activators and passivators allows forming protective layers with high corrosion resistance.

KEYWORDS:

corrosion, steel, potentiostatic anodic polarization, oxidation, molten alkali metal carbonates