Effects of High Thermal Conductivity Substances on Corrosion Behavior of Waterborne Epoxy Zinc-Rich Coatings

The effects of high thermal conductivity substances on the corrosion resistance of aqueous epoxy zinc-rich coatings were mainly investigated by electrochemical impedance spectroscopy (EIS). The surface morphology and roughness of the samples after EIS test were analyzed by 3D laser microscopy. The protective performance of coatings containing different amounts of high thermal conductivity substances was further analyzed by salt spray test. The results showed that when the addition amount of high thermal conductivity material was 1%-4%, the porosity of the coating was low, and the coating had excellent impermeability at the initial stage of immersion. The coating with 8% high thermal conductivity material had relatively high porosity, low impedance value, high roughness and poor protection performance. The coating with 1% high thermal conductivity material had the most excellent anti-corrosion performance.