Microbiologically Induced Corrosion Action on Al-6Mg-Zr and Al-6Mg-Zr-Sc

摘要

The corrosion behaviors of Al-6Mg-Zr and Al-6Mg-Zr-Sc in sulfate-reducing bacteria(SRB) solution in the anaerobic environment were studied by electrochemical, microbiology and surface analysis methods. It is found that the oxide film is more compact resulting in the open circuit potential shifting about 100 mV positively due to the addition of Sc. On the other hand, it is demonstrated that pitting sensitivity of Al-6Mg-Zr-Sc alloy in the SRB solution is decreased and its microbiologically influenced corrosion resistance is improved. But the alloy with Sc addition is sensitive to SRB. The pitting corrosion occurring on both alloys surface under the comprehensive action of the metabolism of SRB is observed by SEM. It is obtained by EDS that the corrosion degree increases with time and the corrosion is furthered by the depositing of product and the dissolution of metals.