INFLUENCE OF Al CONTENT AND ASSOCIATED β-PHASE MORPHOLOGY ON CORROSION PROPERTIES OF Mg/Al ALLOYS

Yıl 2017, Sayı: 1, 178 - 186, 09.11.2017

Sennur Candan Ercan Candan

Öz

The influence of the Al content and associated β
morphology on the corrosion of Mg alloys has been studied using AZ41 and AZ91
series Mg alloys and compared with the corrosion of non Al containing Mg alloy
(i.e AZ01). Scanning
electron microscopy (SEM) was used for microstructural examinations. The
corrosion behaviors were evaluated by immersion tests and potentiodynamic
polarization measurements in 3.5% NaCl solution. The globular shaped β
intermetallic phases were present in AZ41 alloy whereas they were transformed
into a more coarsened lamellar or partially divorced β eutectics in AZ91
alloys. The results
showed that the influence of Al addition on corrosion resistance was more
pronounced up to 4 wt% (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 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.

Anahtar Kelimeler

Mg alloy, AZ series alloys, casting, corrosion

Kaynakça

• Boby, A., Srinivasan, A., Pillai, U. T. S., Pai, B. C. (2015). Mechanical characterization and corrosion behavior of newly designed Sn and Y added AZ91 alloy. Materials and Design, 88, 871-879. Candan ,S., Unal, M., Koc, E., Turen, Y., Candan, E. (2011). Effects of titanium addition on mechanical and corrosion behaviours of AZ91 magnesium alloy. Journal of Alloys and Compounds,509, 1958-1963. Candan, S., & Candan, E. (2017). A Comparative study on corrosion of Mg-Al-Si alloys. Transactions of Nonferrous Metals Society of China, (In press). Candan, S., Celik, M., Candan, E. (2016). Effectiveness of Ti-micro alloying in relation to cooling rate on corrosion of AZ91 Mg Alloy. Journal of Alloys and Compounds, 672, 197-203. Candan, S., Unal, M., Turkmen, M., Koc, E., Turen Y., Candan, E. (2009). Improvement of mechanical and corrosion properties of magnesium alloy by lead addition. Materials Science and Engineering A, 501, 115-118. Cheng, Ying-Liang, Qin, Ting-Wei, Wang, Hui-Min, Zhang, Zhao. (2009). Comparison of corrosion behaviors of AZ31, AZ91, AM60 and ZK60 magnesium. Transactions of Nonferrous Metals Society of China, 19, 517-524. Cramer, S.D., & Covino, B.S., Jr (Eds). (1987). ASM International, Corrosion, Metals Handbook, Materials Park. Ohio, OH: The Materials International Society. Friedrich, H. E., & Mordike, B. L. (2006). Magnesium technology metallurgy, design data, applications. 1st ed. Berlin: Springer-Verlag. Ghali, E., (2010). Corrosion resistance of aluminum and magnesium alloys, understanding, performance and testing. 1st ed. New Jersey: Wiley Publishing. Gusieva, K., Davies, C. H. J., Scully, J. R., Birbilis, N. (2015). Corrosion of magnesium alloys: the role of alloying. International Materials Reviews, 60, 169-194. Hehmann, F., Froes, F. H., Young, W. (1987). Rapid solidification of aluminium, magnesium and titanium. Journal of Metals, 39(8), 14-21. Koc, E. (2013). An investigation on corrosion dependent mechanical behaviours of biodegradable magnesium alloys. Karabuk: Karabuk University, Institute of Science and Technology. Liu, M., Zanna, S., Ardelean, H., Frateur, I., Schmutz, P., Song, G.L., Atrens, A., Marcus, P. (2009). A first quantitative XPS study of the surface films formed, by exposure to water, on Mg and on the Mg-Al intermetallics: Al3Mg2 and Mg17Al12 . Corrosion Science, 51, 1115-1127. Lunder, O., Lein, J. E., Aune, T. K., Nisancıoglu, K. (1989). The role of magnesium aluminuim (Mg17Al12) phase in the corrosion of magnesium alloy AZ91. Corrosion, 45, 741-748. Luo, A. A., & Sachdev, A. K. (2012). Applications of magnesium alloys in automotive engineering, C.Bettles, M. Barnett, Wrought Magnesium Alloys (pp. 393-426). Woodhead Publishing. Manuel, M. V., Singh, A., Alderman, M., Neelameggham Nr., (2015). Magnesium technology, M.V. Manuel, A. Singh, M. Alderman, N.R. Neelameggham. Wiley-TMS Publishing. Pardo, A., Merino, M. C., Coy, A. E., Viejo, F., Arrabal, R., Feliú, S. Jr. (2008). Influence of microstructure and composition on the corrosion behaviour of Mg/Al alloys in chloride media. Electrochimica Acta, 53, 7890-7902. Pekguleryuz, M., (2013). Alloying behavior of magnesium and alloy design, M.O. Pekguleryuz, K.U. Kainer, A.A. Kaya. Fundamentals of Magnesium Alloy Metallurgy (pp. 152-196). Woodhead Publishing. Salman, S. A,, Ichino, R., Okido, M. (2010). A Comparative electrochemical study of AZ31 and AZ91magnesium alloy. International Journal of Corrosion, 1-7. Samaniego, A., Llorente, I., Feliu. Jr S. (2013). Combined effect of composition and surface condition on corrosion behaviour of magnesium alloys AZ31 and AZ61. Corrosion Science, 68, 66-71. Shi, Z., Liu, M., Atrens, A. (2010). Measurement of the corrosion rate of magnesium alloys using tafel extrapolation. Corrosion Science, 52, 579-588. Singh. I. B., Singh, M., Das, S. (2015). A comparative corrosion behavior of Mg, AZ31 and AZ91 alloys in 3.5% NaCl solution. Journal of Magnesium and Alloys,3, 142-148. Tanverdi, A. (2005). Effect of solidification rate and Si and Y additions on corrosion behavior of AZ91 Mg alloy. Eskisehir: Osmangazi University, Institute of Science and Technology. Wang, Lei., Shinohara, T., Zhang, Bo-Ping. (2012). Electrochemical behaviour of AZ61 magnesium alloy in dilute NaCl solutions. Materials and Design, 33, 345-349.