All solutions for corrosion studies were prepared with NaCl (≥99.5) and KMnO4 received from Chemsolute (Th. Geyer Polska) and ChemPur (Poland) using deionized water with a resistivity of at least 18.2 MΩ cm. As a reference corrosion solution, 0.05 M NaCl solution was selected. This concentration of salt was selected based on our previous studies of inorganic corrosion inhibitors of Mg and Al alloys . In experiments with the permanganate inhibitor, the concentration of the inhibitor varied in the range of 5-150 mM. Electrochemical experiments were carried out using a P-40X potentiostat/galvanostat and an Autolab PGSTAT302N potentiostat/galvanostat with an FRA32M module for OCP, EIS, and polarization measurements and a two-channel Biologic SP-300 potentiostat for DEIS measurements. Classical electrochemical measurements were performed on samples with the working area of 1.0 cm 2 in the following order: the open-circuit potential (OCP) stabilization for 1000 s, standard EIS measurement, low-amplitude polarization resistance measurement, and potentiodynamic polarization measurement. A three-electrode setup with a bottom mounting of the working electrode, a saturated Ag/AgCl reference electrode, and a Pt-mesh counter electrode was used. For the pH monitoring, a Schott Titroline Easy titrator was used and connected to PC for data transfer. The pH electrode was placed close to the metal surface. A set of pH data was recorded in a separate measurement series without vigorous stirring to avoid measurement fluctuations.