Influence of Si Content on the Characteristics of Al-Zn-In-Mg-Ti Sacrificial Anode

The influence of Si on the corrosion behaviour of Al-Zn-In-Mg-Ti alloy was investigated by the microstructure observation and electrochemical measurements in order to improve its corrosion non-uniform and electrochemical properties. The results show that the current efficiency of Al-5Zn-0.02In-1Mg-0.05Ti-0.09Si (wt.%) alloy corroded uniformly reaches 92%. It presents the property of low resistance and high capacitance. While the Si content exceeds 0.12 wt.%, the resistance of active dissolution increases gradually. The current efficiency decreases obviously. The results indicate that the electrochemical characteristics and corrosion uniformity can be improved significantly after adding 0.09 wt.% Si into Al-Zn-In-Mg-Ti alloy.