Abstract
UDC 66.087:669-034.721
DOI https://doi.org/10.52577/eom.2022.58.6.19
The article presents the findings on the effect of the substrate pre-impregnation in the cerium (III) nitrate and glycerin aqueous solutions on the corrosion-protective properties of the coatings generated on the magnesium alloy MA8 surface by microarc oxidation. The coatings were formed in the A-K mode from a silicate-alkaline base electrolyte solution containing compounds with fluoride ions. The corrosion resistance of the magnesium alloy ensured by oxide-ceramic coatings and without them was evaluated by the electrochemical corrosion parameters: corrosion potential, corrosion current density, and polarization resistance. The study has shown that the coatings formed on the surface of the magnesium alloy MA8 provide effective anticorrosive properties of the substrate of MA8 in the solutions containing chloride ions. It was established that the preliminary impregnation of a substrate made of magnesium alloy MA8 in aqueous solutions of cerium (III) nitrate and glycerin affects the mechanism of the resulting corrosion damage.
Keywords: microarc oxidation, potentiodynamic polarization curves, corrosion potential, corrosion current density, polarization resistance, corrosion protection properties, magnesium alloy, elemental composition, morphology.