Characterization of the corrosion behaviour of modified 3003 aluminium finstock alloys made by direct chill casting and twin roll casting routes used in car heat exchange systems using electrochemical tests

Abstract

Purpose: In this work, corrosion behaviour of the three different 70 mu m thickness finstock foils: commercially available Al-Si-Mn contained 3003 aluminium (3003 DC), and Zinc added 3003 aluminium (3003 DC-Zn) alloys made by direct chill (DC) caster process and twin roll cast Zn added 3003 aluminium (3003 TRC-Zn) alloys was evaluated. Theory and Methods: Advanced electrochemical corrosion test techniques such as open circuit potential (OCP), potantiodynamic curves and electrochemical impedance spectroscopy (EIS) in 1 Molar NaCI + H2O2 solution environment were performed. Also, surface characterization of the samples used in this study was performed by 3D profilometer, scanning electron microscopy (SEM) added EDS tool, and chemical composition analysis methods such as optical spectroscopy and X-ray diffraction before and after electrochemical corrosion tests. Results: The results of the study showed that the surface roughness and corrosion rate and impedance values of the 3003 aluminium alloy modified with Zn (3003 TRC-Zn) produced by TRC method had higher values than that of the 3003 DC and 3003 DC-Zn samples. Conclusion: It was concluded that the 3003 TRC-Zn would be of use as a sacrifice metal in car heat exchanger systems, due to its desired poor corrosion resistance.