Abstract
The effect of continuous rotation evolutional controHCREO) on the pitting corrosion resistance of anodized Al-Mg alloy was investigated by electrochemical techniques in a solution containing 0.2 mol/L of AICI3 and by surface analysis. The potentials for pitting corrosion of anodized Al-Mg alloy was evidently shifted to the less noble direction by CREO and the time required before initiating pitting corrosion was shorter with CREO, indicating that the corrosion resistance with CREO was worse than without. The precipitates of Fe-Al intermetallic compounds remained in anodic oxide films of Al-Mg alloy. Cracks occurred in the anodic oxide films through the precipitates during initial pitting corrosion. The pitting corrosion was accelerated by cracks. The internal stress present in the anodic oxide films of the alloys with CREO was higher than without. It is assumed that the pitting corrosion is promoted by these cracks as a result of the higher internal stress resulting from the CREO.
Original language | English |
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Pages (from-to) | 1985-1991 |
Number of pages | 7 |
Journal | Materials Transactions |
Volume | 50 |
Issue number | 8 |
DOIs | |
State | Published - Aug 2009 |
Keywords
- Aluminum-magnesium alloy
- Anodization
- Continuous rotation evolutional control
- Pitting corrosion