Localized corrosion of the Mg alloys with inhibitor-containing coatings: SVET and SIET studies

• The way of self-healing coating formation on the Mg alloy has been suggested.
• SVET and SIET were used for determining the kinetics of the self-healing process.
• The self-healing mechanism has been studied and described in this work.
• Inhibitors ability to prevent the corrosion process in the defect zone was studied.
• Self-healing composite coating avert intensive destruction of the magnesium alloy.

The way of self-healing coating formation at the surface of magnesium alloys on the base of plasma electrolytic oxidation method (PEO) has been suggested. Scanning Vibrating Electrode Technique (SVET) and Scanning Ion-Selective Electrode Technique (SIET) were used for determining the kinetics and mechanism of the self-healing process. The treatment of the PEO-layer by the solution containing 8-hydroxyquinoline enables one to decrease the current density of the composite coating in 30 times (3.2 μA cm−2) in the corrosion-active environment in comparison with the base PEO-coating (100 μA cm−2) and avert the intensive destruction of the material.