Abstract
The electrochemical behaviour of Zn - (0.5%) Pb alloy in 1.0 M solutions of different halide ions (pH=3) was studied using capacitance, potential and polarization measurements. The experimental results indicate that the corrosion process decreases in the order: Br- > Cl- > I- > F-. The highest corrosion current in case of Dr ion was attributed to the specific adsorption of the ion and formation of Zn-bromo complex. Also the corrosion process increases as the 136 ion concentration increases as well as the increase of temperature. The thermal coefficient and the activation energy were estimated and found to be -0.444 mV/deg and 1.663 kJ/deg respectively. The negative thermal coefficient of the alloy indicates that the rise of temperature leads to depletion of O-2 which acts as depolarizer and consequently the steady state potential was shifted to more negative value as the temperature increases.