Aluminum sacrificial anodes are widely used in cathodic protection of steel structures in sea water. In the present work, samples of Al-5.3 at.% Zn-x at.% Mg (x = 5.5-8.5) alloys were microstructurally and electrochemically characterized to evaluate their performance as Al-sacrificial anodes for cathodic protection of structures exposed to marine environments. The experiments focussed on the influence of Mg content on electrochemical behavior and efficiency. Mg was used in different concentrations ranging from 5.5 to 8.5 at.%. Short-term electrochemical tests, DNV RP B401, as well as polarization curves and electrochemical impedance spectroscopy were performed to obtain electrochemical behavior and efficiency and to reveal any tendencies to passivation. It is shown that by increasing Mg content an improvement of electrochemical properties of Al-alloy such as current capacity and then electrochemical efficiency can be obtained.
Effect of Mg content on the performance of Al-Zn-Mg sacrificial anodes
Journal of Materials Engineering and Performance ; 16 , 2 ; 229-235
2007
7 Seiten, 20 Quellen
Article (Journal)
English
Aluminiumverbindung , AlZnMg-Legierung , Anodenwerkstoff , Baustahl , elektrochemische Reaktion , Elektrodenwerkstoff , Gießen , kathodischer Schutz , Magnesiumzusatz , Meerwasserkorrosion , Mikrostruktur , Mikrostrukturtechnik , Opferanode , Passivierung , Stahlbau , Stromausbeute , Umgebungsbedingung