Effect of Additives on Anticorrosion Ability of Cr3+ Passivated Film of Zinc-plated Layer

To improve anti-corrosion properties of Cr3+ passivated film of Zinc-plated layer,effects of additives such as oxalic acid,glycerolmon ostearate,sodium dodecyl benzene sulfonate(SDBS) and sodium dodecyl sulfonate(SDS) on anti-corrosion properties of Cr3+ passivating film had been studied by using electrochemical methods,5%NaCl immersion tests etc.The anti-corrosion properties of Cr3+ passivated film were approximate to those of Cr6+ passivated film when composite additive of SDS (0.6g/L) and oxalic acid (1.0g/L) were added into Cr3+ passivation solution.