ISSN: 1003-6326
CN: 43-1239/TG

Vol. 28    No. 4    April 2018

Comparative study on corrosion behaviors of Mg-Al-Zn alloys
(Department of Mechanical and Manufacturing Engineering, Bilecik Seyh Edebali University, Bilecik, Turkey)
Abstract: A comparative study on corrosion behaviors of various Mg-Al-Zn alloys (AZ21, AZ41, AZ61 and AZ91 series, cast under same cooling conditions and controlled alloying composition) was carried out. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used for microstructural examinations. The corrosion behaviors were evaluated by immersion tests and potentiodynamic polarization measurements in 3.5% NaCl solution. The results showed that the influence of Al addition on corrosion resistance was more pronounced up to 4% (i.e. AZ41) above which its influence was at less extent. The deterioration of the corrosion resistance of the alloys, at higher Al contents, was attributed to the amount and morphology of β-Mg17Al12 intermetallics and the interruption of continuity of the oxide film on the surface of the alloys owing to coarsened β intermetallics.
Key words: Mg alloy; AZ series alloys; casting; corrosion
Superintended by The China Association for Science and Technology (CAST)
Sponsored by The Nonferrous Metals Society of China (NFSOC)
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