Effects of Drying Temperature on Phase Compositions and Properties of Mechanical Galvanizing Coatings

Zinc coatings on Q235 steel prepared by mechanical galvanizing were dried at 100 ℃,200 ℃ and 300 ℃ for 1 h respectively.Surface hardness of the coating was studied by surface Rockwell hardness tester,and the porosity was tested by iron reagent method.XRD was used to study the phase compositions of the coatings.The effect of drying temperature on the corrosion resistance of the coatings was studied by salt spray test and potentiodynamic polarization.The results show that no alloy compounds or solid solution formed in the coating in the temperatures range of 100-300 ℃,and drying temperature had no effects on surface hardness,porosity and corrosion resistance of the coatings.