Electrochemical corrosion performance of eutectic Al-Si automotive alloy in 0.1 M and 0.2 M NaCl solution

Abstract Corrosion behavior of eutectic Al-Si automotive alloy is investigated in different strengths of 0.1 M and 0.2 M NaCl solution at room temperature. Alloy with Si as trace impurity is also considered for the comparison of the property. The study is done by electrochemical method, using potentiodynamic polarization measurements and electrochemical impedance spectroscopy (EIS) techniques. The alloy surfaces are characterized by both optical microscopy and scanning electron microscopy. The results indicate that Si addition improves the corrosion performance of the Al-Si automotive alloy and this improvement is more pronounced in higher corrosive environments. The corrosion rate along with current density (I corr ) of trace Si added alloy showed higher value than that of higher Si added alloy. The…