S.M Maroofi - Faculty of Polymer Engineering & Color Technology, Amirkabir University of Technology, Tehran, Iran
A.A Sabbaghalvani - Faculty of Polymer Engineering & Color Technology, Amirkabir University of Technology, Tehran, Iran
H Eivaz Mohammadloo - Faculty of Polymer Engineering & Color Technology, Amirkabir University of Technology, Tehran, Iran
A Aardari - Researcher in REEf industrial group, Isfahan, Iran

In the present research, anti-corrosion resistance of the zinc phosphate conversion coating on CRS substrates with differentsolutionpH (from 1.7 to 5.7) was studied, using direct current (DC) polarization and electrochemical impedance spectroscopy (EIS). Electrochemical results revealed that the best corrosion resistance from zinc phosphate conversion coating was obtained inpH=2.7. Polarization resistance (Rp) increased to the value of 32.34 kΩ.cm2 which is 83 times higher than the bare sample polarization resistance (Rp: 0.39kΩ.cm2).

zinc phosphate, conversion coating, DC polarization, EIS