The Corrosion Mechanism of Zn-5%Al-0.3%Mg Coating
A new hot dip Zn-5%Al-0.3%Mg alloy coating was performed on cold rolled common steel. The hot-dip process was executed by self-made hot dip galvanising simulator (China patent, No.201010160353). The corrosion resistance of alloy-coated steels was detected by neutral salt spray test . SEM and EDS test results demonstrate that Mg is mainly distributed in the crystal boundary. XRD test results shows corrosion product of Zn-5%Al-0.3%Mg alloy coating is mainly Zn5(OH)8Cl2•H2O. The characteristic of Zn5 (OH)8Cl2•H2O is dense and insoluble, so it is protective. In order to study the anticorrosion mechanism, all the tests of the Zn-5%Al-0.3%Mg alloy were carried out with Zn-5%Al coating together.
Zhengyi Jiang, Shanqing Li, Jianmin Zeng, Xiaoping Liao and Daoguo Yang
B. Gao et al., "The Corrosion Mechanism of Zn-5%Al-0.3%Mg Coating", Advanced Materials Research, Vols. 189-193, pp. 1284-1287, 2011