Cathodic disbanding improvement of mild steel using zirconium conversion coating

In this study, the effect of zirconium-based surface treatment on the cathodicdisbonding resistance and adhesion performance of an epoxy coated mild steel substrate was investigated. The obtained data from pull-off, cathodicdisbonding test and electrochemical impedance spectroscopy (EIS) indicated that the zirconium conversion layer significantly improved the adhesion strength and cathodicdisbonding resistance of the epoxy coating. This may be attributed to formation of some polar zirconium compounds on the surface and increment of surface roughness, that were evident in the results of field emission scanning electron microscopy (FE-SEM) and Atomic force microscopy (AFM) respectively.