Corrosion analysis of Al–Zn–In–Mg–Ti–Mn sacrificial anode alloy

• Published in: Journal of alloys and compounds Vol. 496; no. 1; pp. 110 - 115
• Main Authors: Ma, Jingling, Wen, Jiuba
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 30.04.2010; Elsevier
• Subjects: Al alloy; Aluminum base alloys; Aluminum oxide; Applied sciences; Corrosion; Corrosion mechanisms; Corrosion potential; Exact sciences and technology; Immersion; Metals. Metallurgy; Pitting (corrosion); Precipitates; Precipitation; Sacrificial anode; SEM; Sacrificial anode; SEM; Al alloy; Corrosion; Precipitates; Scanning electron microscopy; Corrosion mechanism; Aluminium base alloys; Electrochemical corrosion; Corrosion potential; Precipitate; Dispersive spectrometry; Pitting corrosion; Precipitation; Transmission electron microscopy
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2010.02.174

The corrosion behaviour of Al–5Zn–0.02In–1Mg–0.05Ti–0.5Mn (wt%) alloy was investigated by SEM, EDX and TEM. The results show that there exist different corrosion types of the alloy in 3.5% NaCl solution with immersion time. At the initial stage of immersion, pitting predominate the corrosion around precipitates. The major precipitates of the alloy are MgZn 2 and Al 6Mn particles. The corrosion potential of the bulk MgZn 2 alloy is negative with respect to that of the α-Al and the bulk Al 6Mn alloy, so the MgZn 2 precipitate can act as activation centre, make the aluminum oxide film breakdown and cause the pitting corrosion. In the late stage, it turns out to be a uniform corrosion due to the control of dissolution precipitation of In and Zn ions.