CORROSION STABILITY IN SALT MEDIUM OF STAINLESS STEEL AND CARBON STEEL, USING DIFFERENT OXIDE SOL GEL COATINGS
Three types of oxide sol gel coatings: TiO2, CeO2 and TiO2/CeO2 composite were deposited by sol gel method on stainless steel and carbon steel. The morphology was examined by means of Scanning electron microscopy (SEM). X-ray diffraction analyses (XRD) were applied to investigate the phase composition. The corrosion resistances of the coatings were studied by evaluation of the weight loss in NaCl medium for 1200 hours. The surface of the TiO2 samples were relatively dense with a few surface nanocrystals and after tests does not shown any signs of corrosion. Тhe composite TiO2/CeO2 samples possess deep cracks which evidently favor the attacks in corrosion medium. Ceria and titania coatings deposited on stainless steel have zero weight loss in corrosive medium. The TiO2 coatings could also effective protect carbon steel, while the TiO2/CeO2 and CeO2 coatings exhibited lower corrosion resistance.