Electrophoretic deposition and corrosion behavior study of aluminum coating on AZ91D substrate

Document Type : Research Paper


Materials Engineering Department, University of Tabriz, Tabriz, Iran.


Aluminum coating was prepared on AZ91D magnesium alloy substrate using the electrophoretic deposition (EPD) method in absolute ethanol solvent. In order to determine the optimal concentration of AlCl<sub>3</sub>.6H<sub>2</sub>O additive, the zeta potential and size of particles in the suspension were measured in the presence of different concentrations of AlCl<sub>3</sub>.6H<sub>2</sub>O. The results showed that an appropriate coating is obtainable in the presence of  0.6 mM AlCl<sub>3</sub>.6H<sub>2</sub>O as an additive. The effects of applied voltage, deposition time, and additive concentration on deposition weight, deposition thickness, and coating morphology were also studied. A uniform coating with smaller pores and higher density was obtained at the additive concentration of 0.6 mM, deposition time of 18 min, and applied voltage of 70 V. The thickness of this coating was measured at about 256.91 µm. According to the results of corrosion behavior studies, the corrosion current density was measured at 29.16 and 12.85 µA/cm2 for uncoated and aluminum-coated AZ91D alloy, respectively.


  • In this study, aluminum powder coating was developed on AZ91D magnesium alloy substrate by electrophoretic deposition.
  • To determine the optimal condition of deposition, the effects of AlCl<sub>3</sub>.6H<sub>2</sub>O concentration, applied voltage, and deposition time were investigated.
  • A well-stabilized suspension and a uniform deposition were obtained at the AlCl<sub>3</sub>.6H<sub>2</sub>O concentration of 0.6 mM, applied voltage of 70 V and deposition time of 18 min.


[1] F. Czerwinski, Magnesium Alloys: Corrosion and Surface Treatments, InTech Publisher, London, 2011, pp. 195.
[2] G.L. Song, "Electroless" deposition of a pre-film of electrophoresis coating and its corrosion resistance on a Mg alloy, Electrochim. Acta, 55 (2010) 2258-2268.
[3] W. Feng, W. Yue, M.Ping-li, Y.U. Bao-yi, G. Quan-ying, Effects of combined addition of Y and Ca on microstructure and mechanical properties of die casting AZ91 alloy, T. Nonferr. Metal. Soc. 20 (2010) s311-s317.
[4] Y. Zhan, Z. Hong-yang, H. Xiao-dong, J. Dong-ying, Effect of elements Zn, Sn and In on microstructures and performances of AZ91 alloy, T. Nonferr. Metal. Soc. 20 (2010) s318-s323.
[5] A. Nold, J. Zeiner, T. Assion, R. Clasen, Electro-phoretic deposition as rapid prototyping method, J. Eur. Ceram. Soc. 30 (2010) 1163-1170.
[6] Y. Tao, T. Xiong, C. Sun, L. Kong, X. Cui, T. Li, G.L. Song, Microstructure and corrosion performance of a cold sprayed aluminum coating on AZ91D magnesium alloy, Corros. Sci. 52 (2010) 3191-3197.
[7] S. Fleming, An Overview of magnesium based alloys for aerospace and automotive applications, [Dissertation] Rensselaer Polytechnic Institute, Hartford, CT August, 2012.
[8] A. Shahriari, H. Aghajani, Electrophoretic deposition of 3YSZ coating on AZ91D using an aluminum interlayer, Prot. Met. Phys. Chem. S. 53 (2017) 518-526.
[9] M. Ahmadi, H. Aghajani, Structural characterization of YSZ/Al2O3 nanostructured composite coating fabricated by electrophoretic deposition and reaction bonding, Ceram. Int. 44 (2018) 5988-5995.
[10] S. Candan, M. Unalb, E. Koc, Y. Turen, E. Candan. Effects of titanium addition on mechanical and corrosion behaviours of AZ91 magnesium alloy, J. Alloy. Compd. 509 (2011) 1958-1963.
[11] K. Yang, Z. Jiang, J. Chung, Electrophoretically Al-coated wire mesh and its application for catalytic oxidation of 1,2-dichlorobenzene, Surf. Coat. Tech. 168 (2003) 103-110.
[12] G. Lee, S. Pyun, C. Rhee, A study on electrophoretic deposition of Ni nanoparticles on pitted Ni alloy 600 with surface fractality, J. Colloid Interf. Sci. 308 (2007) 413.
[13] X. Guo, X. Li, H. Li, D. Zhang, C. Lai, W. Li, A Comprehensive investigation on the electrophoretic deposition (EPD) of Nano-Al/Ni energetic composite coatings for the combustion application, Surf. Coat. Tech. 265 (2015) 83-91.
[14] L. Besra, M. Liu, A review on fundamentals and applications of electrophoretic deposition (EPD), Prog. Mater. Sci. 52 (2007) 1-61.
[15] K. Liu, Q. Liu, Q. Han, G. Tu, Electrodeposition of Al on AZ31 magnesium alloy in TMPAC-AlCl3 ionic liquids, T. Nonferr. Met. Soc. 21 (2011) 2104-2110.
[16] ASM International Handbook Committee, ASM Handbook of properties and selection: Nonferrous alloys and special-purpose materials, Vol. 2, ASM International, Ohio, 1990.
[17] J. Ma, W. Chen, Deposition and packing study of sub-micron PZT ceramics using electrophoretic deposition, Mater. Lett. 56 (2002) 721-727.
[18] N. Sato, M. Kawachi, K. Noto, N. Yoshimoto, M. Yoshizawa, Effect of particle size reduction on crack formation in electrophoretically deposited YBCO films, Physica C, 357-360 (2001) 1019-1022.
[19] Z. Wang, J. Shemilt, P. Xiao, Fabrication of ceramic composite coatings using electrophoretic deposition, reaction bonding and low temperature sintering, J. Eur. Ceram. Soc. 22 (2002) 183-189.
[20] L. Yang, X. Wu, D. Weng, Development of uniform and porous Al coatings on FeCrAl substrate by electrophoretic deposition, Colloid. Surface. A, 287 (2006) 16-23.
[21] S. Kim, S. Cho, J. Lee, S. Samal, H. Kim, Relationship between the process parameters and the saturation point in electrophoretic deposition, Ceram. Int. 38 (2012) 4617-4622.
[22] M.G. Fontana, Corrosion engineering, Third Edition, McGraw Hill, New York, 1987.
[23] A. Lasia, Electrochemical impedance spectroscopy and its applications, Springer-Verlag, New York, 2014.