The 120nm coatings of Al and Al-Mg on low carbon steel EN8 have been irradiated with 65keV

6×1016 Ar+2/cm2. Adhesion of the coatings on the substrate is tested. The corrosion potential measurement and immersion test are carried out in acetic acid buffer solution with pH=5.6. The experiments indicate that the corrosion resistance of the sample increases effectively due to the cathodic protection of magnesium in the coating.