Cl(上标 -)浓度对镁－铝合金β相模型合金腐蚀电化学行为的影响

The electrochemical behavior of a model β phase Mg-Al alloy was investigated in solutions with different concentrations of Cl(superscript -) in comparison with model α phase alloy. The results indicated that the increase of Cl(superscript -) concentration may decrease the corrosion potential of β phase. However, there is no distinct in potential difference between β phase and α phase. The β phase may be passivated in solutions with different concentrations of Cl(superscript -). With the increasing of Cl(superscript -) concentration the pitting breakdown potential of β phase slightly lower. There is excess Cl(superscript -) doping the formed corrosion scales on β phase surface as the Cl(superscript -) concentration increases. It is expected that β phase in magnesium-aluminum alloy may play certain role in micro galvanic couple with substrate in atmosphere corrosion in sodium chloride polluted environments.