A corrosion resistant cerium oxide based coating on aluminum alloy 2024 prepared by brush plating

▶ The deposition of rare earth conversion coatings on aluminum alloys and other metals is considered as an effective method to replace chromate conversion coatings which have been prohibited in many fields for their toxicity. ▶ However, most of the reported methods to prepare cerium oxide based coatings were based on electrodeposition or chemical conversion processes. ▶ The addition of hydrogen peroxide results in cerium precipitates and solution instability. ▶ Deposition solutions with H2O2 are also difficult to recycle. ▶ In this study, a cerium oxide-based coating was deposited on aluminum alloy 2024 by brush. ▶ The brush plated cerium oxide based coatings on aluminum alloy showed good corrosion resistance. ▶ H2O2 is not necessary in the brush plating solution. ▶ The influence of the plating parameters on structure and corrosion resistance of the cerium oxide based coatings was studied. Cerium oxide based coatings were prepared on AA2024 Al alloy by brush plating. The characteristic of this technology is that hydrogen peroxide, which usually causes the plating solution to be unstable, is not necessary in the plating electrolyte. The coating showed laminated structures and good adhesive strength with the substrate. X-ray diffraction and X-ray photoelectron spectroscopy analysis showed that the coatings were composed of Ce(III) and Ce(IV) oxides. The brush plated coatings on Al alloys improved corrosion resistance. The influence of plating parameters on structure and corrosion resistance of the cerium oxide based coating was studied.