Microstructure and Properties of MAO Coatings for AZ91D Magnesium Alloy in Varies Work Mode

Abstract:

Micro arc oxidation coatings were prepared on AZ91D magnesium alloy in order to evaluate the role of electrical parameters under different work mode. Taking HV hardness and pit corrosion time as investigation index, the optimum process parameters were obtained through orthogonal experiment method. The morphology of coating was observed by scanning electron microscopy (SEM). The results showed that the coatings with dense and few micro pores can be obtained under constant current and power mode, and this kind coatings are of good corrosion resistance and have HV micro-hardness compared with those under constant voltage mode.

• Periodical: Materials Science Forum (Volumes 747-748)
• Pages: 178-183
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.747-748.178
• Online since: February 2013
• Authors: Xue Jun Cui, Xiu Zhou Lin, Chun Hai Liu, Rui Song Yang, Ming Tian Li
• Keywords: Electrical Parameters, Magnesium Alloy, Micro-Arc Oxidation (MAO), Work Mode

References

[1] C. Blawert, W. Dietzel, E. Ghali, G.L. Song, Review: Anodizing treatments for magnesium alloys and their effect on corrosion resistance in various environments, Adv. Eng. Mater. 2006, 8(6): 511-533.

DOI: 10.1002/adem.200500257

[2] A. Mandelli, M. Bestetti, A. Da Forno, N. Lecis, S.P. Trasatti, M. Trueba, A composite coating for corrosion protection of AM60B magnesium alloy, Surf. Coat. Technol. 205 (2011) 4459-4465.

DOI: 10.1016/j.surfcoat.2011.03.066

[3] I.J. Hwang D.Y. Hwang, Y.G. Ko, D.H. Shin, Correlation between current frequency and electrochemical properties of Mg alloy coated by micro arc oxidation, Surf. Coat. Technol. 206 (2012) 3360-3365.

DOI: 10.1016/j.surfcoat.2012.01.041

[4] R.O. Hussein, P. Zhang, X. Nie, Y. Xia, D.O. Northwood, The effect of current mode and discharge type on the corrosion resistance of plasma electrolytic oxidation (PEO) coated magnesium alloy AJ62, Surf. Coat. Technol. 206 (2011) 1990-(1997).

DOI: 10.1016/j.surfcoat.2011.08.060

[5] X.J. Cui, C.H. Liu, R.S. Yang, X.Z. Lin, M. Gong, Preparation and Characterization of Phosphate Film for Magnesium Alloy AZ31, Physics Procedia 25(2012): 194-199.

DOI: 10.1016/j.phpro.2012.03.070

[6] J. Chen, Y.W. Song, D.Y. Shan, E.H. Han, Study of the in situ growth mechanism of Mg-Al hydrotalcite conversion film on AZ31 magnesium alloy, Corros. Sci. 63 (2012): 148-158.

DOI: 10.1016/j.corsci.2012.05.022

[7] R.H. Zhang, J. Liang, Q. Wang, Preparation and characterization of graphite-dispersed styrene-acrylic emulsion composite coating on magnesium alloy, Appl. Surf. Sci. 258 (2012): 4360-4364.

DOI: 10.1016/j.apsusc.2011.12.113

[8] H. Chen, G.H. Lv, G.L. Zhang, H. Pang, X.Q. Wang, H.J. Lee, S.Z. Yang. Corrosion performance of plasma electrolytic oxidized AZ31 magnesium alloy in silicate solutions with different additives, Surf. Coat. Technol. 205 (2010) S32-S35.

DOI: 10.1016/j.surfcoat.2010.03.032

[9] Y.M. Tang, X.H. Zhao, K.S. Jiang, J. Chen, Y. Zuo, The influences of duty cycle on the bonding strength of AZ31B magnesium alloy by microarc oxidation treatment, Surf. Coat. Technol. 205 (2010) 1789-1792.

DOI: 10.1016/j.surfcoat.2010.05.016

[10] Y. Ma, H. Zhan, Y.Z. Ma, W.L. Lu, J.Y. Feng, W. Gao, Effects of electrical parameters on microstructure and corrosion resistance of micro-arc oxidation coatings on AZ91D magnesium alloys, Trans. Nonferrous Met. Soc. China 20(2010)8: 1467-1473.

[11] R.F. Zhang, D.Y. Shan, E.H. Han, Z.L. Zeng, Status and prospect of anodization on magnesium and its alloys, Trans. Nonferrous Met. Soc. China 16(2006)7: 1136-1448.