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

Document Type : Research Article


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.


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