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Enormous economic lost and social hazard are caused by metal corrosion.Electrodeposited Zn and Zn-Fe alloy have been applied widely to protect steel from corrosion,but there are still some problems need to be solved,such as pollution of chromate treatment,low corrosion resistance,high hydrogen embrittlement,etc.In order to avoid pollution of chromatizing with electrodeposited Zn and Zn-Fe alloy,and keep or even improve the corrosion resistance of galvanized steel simultaneously,Zn-Fe-SiO2 composite coatings are prepared in this paper.Zinc based coatings with Fe 2.5%(mass) and SiO20.5 % (mass) are deposited from sulfate bath,and the bath composition and operating conditions are:FeSO4·7H2O 30 g/L,ZnSO4·7H2O 50 g/L,(NH4)2SO460 g/L,C6H8O7·H2O 30 g/L,Al2(SO4)3·12H2O 6 g/L,Ascorbic acid,2 g/L,SiO2 30 g/L,pH 2.5~3,Current density 2.5 A/dm2,Temperature 20~30 ℃.Zinc based coatings with Fe 0.6 % (mass) and SiO2 0.5 % (mass) are deposited from chloride bath,and the bath composition and operating conditions are:ZnCl2 90 g/L,FeSO4·7H2O 8 g/L,KCl 220 g/L,Ascorbic acid 1 g/L,SiO2 2 g/L,pH 4~5,Current density 1.5 A/dm2,Temperature 20~30 ℃.