Study on Epoxy Resin/Multi-Walled Carbon Nanotubes Conductive Coating on Az31 Magnesium Alloy After Micro-Arc Oxidation

After micro-arc oxidation, the surface properties of AZ31 magnesium alloy have been improved. However, micro-arc oxidation treatment leads to high insulation, which limits its application in electronic devices. To increase conductivity, a conductive coating was developed by adding multi-walled carbon nanotubes (MWCNTs) to the epoxy resin. The microstructure and performance of the coating were tested by SEM, thermogravimetric analyzer, four-probe conductivity meter, high-temperature friction and wear tester, and electrochemical workstation. The results indicate that the optimal conductivity with a resistivity of 303[Formula: see text][Formula: see text]m is obtained when the MWCNT content is at 4[Formula: see text]wt%. In addition, MWCNTs are filled with a network structure of epoxy resin, which increases the density of the coating and enhances their wear and corrosion resistance.