Study on Chromium-Free Color Passivation for Zinc Coating Treated with Silicate
This paper mainly focuses on how the silicate liquid composition of chromium-free color passivation affects on passivation result, and confirmes the optimum passivation conditions, and uses two zinc plating system of alkaline and acid deposition. Silicate passivation system is compared with hexavalent chromium passivation technology and the results showed that: the appearance and corrosion resistance of passive films formed on zinc coatings plated with alkaline system are better than samples plated with acid system, and have the same corrosion resistanc with hexavalent chromium passivation. The silicate passivation films can keep 200 hours with no white rust in neutral salt spray test.
Zhengyi Jiang, Xianghua Liu and Jinglong Bu
X. K. Yang et al., "Study on Chromium-Free Color Passivation for Zinc Coating Treated with Silicate", Advanced Materials Research, Vols. 154-155, pp. 1301-1304, 2011