Protection against corrosion in marine environments of AA6060 aluminium alloy by cerium chlorides

• Published in: Journal of alloys and compounds Vol. 491; no. 1; pp. 223 - 229
• Main Authors: Allachi, H., Chaouket, F., Draoui, K.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 18.02.2010; Elsevier
• Subjects: Aluminium alloy; Applied sciences; Cerium; Corrosion; Corrosion prevention; Electrochemical techniques; Exact sciences and technology; Inhibition; Metals. Metallurgy; NaCl; Cerium; NaCl; Electrochemical techniques; Aluminium alloy; Inhibition; Corrosion; Scanning electron microscopy; Corrosion mechanism; Aluminium base alloys; Oxide layer; Corrosion protection; Pitting corrosion; Cerium addition; Aqueous solution; Sea water corrosion
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2009.11.042

Lanthanide salts are being considered as an environmentally friendly alternative to the classic systems based on chromates. The addition of small concentrations of cerium chloride to aerated aqueous 3.5% NaCl solution inhibits uniform and pitting corrosion processes of AA6060. Full immersion tests combined with different electrochemical techniques were involved to determine the protection degree and the inhibition character supplied by the cerium ion. Their microscopic and compositional features have been analyzed using SEM and EDS spectra. The results obtained show that the protective layer has heterogeneous composition. An alumina layer covers the aluminium matrix while dispersed cerium-rich islands deposited over the cathodic sites of the alloy. In the case of AA6060, α-Al(Fe,Mn)Si acts as permanent cathodic sites.