Effect of CeCl3 addition on aluminum coatings electrodeposited from a room-temperature molten salt on LA103Z Mg-Li alloy

Electrodeposition of an aluminum coating is an effective approach for improving the corrosion resistance of LA103Z Mg-Li alloy. In this study, aluminum coatings were electrodeposited on LA103Z alloy from an AlCl 3 -Et 3 NHCl ionic liquid electrolyte with CeCl 3 as an additive. The effects of CeCl 3 concentration (1 mmol·L -1 ∼0.1 mol·L -1 ) on the morphology, composition, microstructure, and corrosion resistance of the coatings were systematically investigated. Results show that within the range of 1 mmol·L -1 ∼0.01 mol·L -1 , the coating grain structure became fine and uniform. As the concentration increased to 0.1 mol·L -1 , the Ce content in the coating rose, leading to surface cracks and increased roughness. At a cerium concentration of 5 mmol·L -1 , Ce in the coating is predominantly present as trace amounts of Ce 2 O 3 and CeO 2 . Polarization measurements conducted in a 3.5 % NaCl solution reveal a corrosion potential of -1.43 V and a corrosion current density of 34.88 μA·cm -2 .