Effect of surface modification of Cu with Ag by ball-milling on the corrosion resistance of low infrared emissivity coating

The corrosion resistance of low infrared emissivity copper/polyurethane (Cu/PU) coating was markedly improved by surface modification of Cu with silver (Ag) using a ball-milling method. For the purpose of clarifying the effect of the surface modification, the phase and morphology of as-prepared products were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the corrosion behavior was investigated with potentiodynamic polarization and electrochemical impedance spectra (EIS). As a result, it was found that Ag was homogeneously distributed in Cu and the encapsulation of oil layer on the surface of Ag-Cu composite powders was formed after ball-milling, therefore, compatibility with organic phase was improved, which often keeps the low infrared emissivity and enhances the anti-corrosion performance of the coating.