Effects of Zn(OH)2 on Corrosion Behavior of Hot Dipped Zn Coating in Freshwater

Abstract

The corrosion behavior of hot dipped Zn coating in freshwater with and without Zn(OH)2 was investigated through weight loss test, polarization curve and impedance spectroscopy. The morphology of the corroded hot dipped Zn coating was analyzed by SEM, meanwhile, the effect of Cl- on corrosion behavior of hot dipped Zn coating in saturated Zn(OH)2 solution was examined using polarization curve. It was found that corrosion product Zn(OH)2 accelerate the corrosion of coating, Cl- promoted dissolution of anodic coating and incrSubscript texteased the conductance of the solution, and the worst corrosion resistance of coating is Cl-concentration of 1%.