Enhancing the Electroplated Chromium Coating for Corrosion Protection of Aluminum by Adding Graphene Oxide

The effect of the addition of graphene oxide (GO) particles to the chromium electroplated coating on the surface of commercially pure aluminum (Al 1100) was studied in this paper. The synthesized coatings microhardness was characterized by the atomic force microscopy, field emission scanning electron microscopy, and the corrosion behavior was evaluated by using polarization and electrochemical impedance spectroscopy in the 3.5 wt % NaCl solution. The obtained Cr/GO nanocomposite shows remarkable improvement in the value of the surface microhardness, and the highest value achieved at the sample composed with 10 wt % of GO equals 1526 HV_0.5. The results gained from polarization and electrochemical impedance microscopy demonstrated that the sample with the 5 wt % of GO has better corrosion resistance, which is due to the coating compactness and active galvanic couples.