Influence Of Zinc Content And Surface Contamination On The Electrochemical Behaviors Of Epoxy Zinc--Rich Primer
Zn粉含量及表面沾污对环氧富Zn漆电化学行为的影响

The effect of zinc powder content and contamination of epoxy zinc-rich primer/substrate interface on the protective performance of the zinc-rich coatings was investigated by means of electrochemical impedance spectroscopy (EIS) and corrosion potential monitoring . The degradation mechanism of the zinc-rich coatings was elucidated . It was shown that effective barrier can not be formed in the coatings with low zinc content. The attack of zinc particles in zinc-rich coatings is explained in terms of diffusion control through the film of zinc corrosion products around the zinc particles. The surface contamination of the substrate is vital to the performance of the organic coatings protecting the substrate steel. The surface contamination will lead to not only the impairment of the performance of the zinc-rich coatings but also the acceleration of the degradation processes of the steel substrate.