Assessment of Corrosion-Resistant Anodic Aluminium Oxide Coating

Sammanfattning

The aim of this project is to investigate the quality of the anodic oxide coating of twotypes of aluminium alloy samples, EN AW-6014 and EN AC-43100, and to identifyappropriate test methods to assess their corrosion resistance properties. The corrosionbehaviors of the anodic oxide coating of the selected aluminium alloys with the surfacestage as-is, anodized, and anodized & scratched are evaluated through standardizedclimate chamber tests, standardized and non-standardized immersion tests, non-standardized climatic cycle tests, and electrochemical tests. The form and extent ofcorrosion that occurs on the alloy samples after the tests are evaluated by visualappearance,surfacemorphology,andthroughcomparisonofcross-sectionalmicroscopic images of samples taken before the test. This study found that impedancetests were easy and quick test methods to check the quality of the anodic oxide layer.The study also concluded that the cyclic testing in artificial seawater and immersiontest in natural seawater at 28 ºC are the most appropriate test methods to assess thecorrosion behavior of the anodic oxide coating of aluminium alloys due to theircapability of identifying the significant differences between surface stages compared tothe pre-test samples.