The effect of composition and thickness on the mechanism and kinetics of filiform corrosion occurring on zinc-aluminium-magnesium coated steel

The effect of coating thickness and composition on the kinetics acetic acid-induced filiform corrosion (FFC) Zinc-Aluminium-Magnesium (ZAM) coated steel is investigated. Scribe defects are created in organic coatings applied to ∼10 μm varying (1−6 wt.%. Al, 1−3 wt. % Mg), fixed (Zn-1.5 Al- 1.5 wt.% Mg) but (5−27 μm). FCC decreases with increasing Al (at thickness. A linear trend exists between iron exposure time. Findings consistent FFC advancing via a penetrative mechanism whereby exposed couples coating.