【摘要】 对镁-铝合金β相模型合金在不同浓度的Cl~-溶液环境中的腐蚀电化学行为进行研究.结果表明,随着Cl~-浓度的增加,β相的自腐蚀电位依次降低.但β相与α相之间的电位差没有随Cl~-浓度的增加递增.β相在不同浓度的Cl~-溶液中均能发生钝化,随Cl~-浓度的增加点蚀击破电位降低,相应表面膜中含Mg的腐蚀产物种类也增多.在不同浓度Cl~-溶液环境中,β相模型合金的腐蚀电化学结果可以揭示β相的微电偶作用.更多还原

【Abstract】 The electrochemical behavior of a modelβphase Mg-Al alloy was investigated in solutions with different concentrations of Cl~- in comparison with modelαphase alloy.The results indicated that the increase of Cl~- concentration may decrease the corrosion potential ofβphase. However,there is no distinct in potential difference betweenβphase andαphase.Theβphase may be passivated in solutions with different concentrations of Cl~-.With the increasing of Cl~- concentration the pitting breakdown potential ofβphase slightly lower.There is excess Cl~- doping the formed corrosion scales onβphase surface as the Cl~- concentration increases.It is expected thatβphase in magnesium-aluminum alloy may play certain role in micro galvanic couple with substrate in atmosphere corrosion in sodium chloride polluted environments.更多还原