The corrosion behaviour of Al-Zn-In-Mg-Ti alloy in NaCl solution

The corrosion behaviour of Al-5Zn-0.02In-1Mg-0.05Ti (wt.%) alloy was investigated by EIS, SEM and EDX. The results show that there exist different corrosion stages of the alloy in 3.5% NaCl solution with increasing time. At the initial stages, pits predominates the corrosion around precipitates with a typical inductive loop at low frequencies in EIS. In the late corrosion, a relative uniform corrosion predominate the corrosion process controlled by the dissolution-precipitation of the In and Zn ions and characterized by the second capacitive loop at low frequencies in EIS. The mud structure appears on the corrosion surface of the alloy.