Effect of octanoic acid-based inhibitors on the corrosion and electrochemical properties of oxide-ceramic coatings B4C–BN–Bi2O3–MnO2 on unalloyed steel

The effect of mixed inhibitors based on octanoic acid and compounds of nitrogen in a negative oxidation state on the corrosion properties of an oxide-ceramic coating with B4C-BN-Bi2O3-MnO2 composition was studied.The coating was synthesized by laser sintering of the powder mixture on the surface of unalloyed low-carbon steel.As a result of laser treatment, an oxideceramic layer with antifriction properties and high hardness was formed on the metal surface.The phase composition and surface topography of the composite obtained were studied.It was found that the corrosion resistance of the composite obtained was smaller under conditions of electrochemical corrosion in neutral buffer solution than that on untreated steel.The inhibitor treatment method was applied to increase the corrosion resistance.Octanoic acid, octanoic acidhexamethylenetetramine, octanoic acidhydrazine hydrate, and octanoic acid -2,4dinitrophenylhydrazine formulations were used as the inhibitors.The inhibitors were applied by impregnation followed by heating the samples to 120°C.All the mixed inhibitors studied improved the corrosion resistance of the material against electrochemical corrosion in neutral borate buffer solution.