含Mg铝合金牺牲阳极在海水环境中组织与性能的相关性

【目的】为了解决深海环境下牺牲阳极材料性能下降的问题,在Al-Zn-In牺牲阳极的基础上添加Mg和Si元素,分析Mg和Si元素对阳极组织与性能的作用机理。【方法】采用金相组织观察、电化学极化曲线测试,探究偏析相、晶粒细化对铝阳极性能的影响。【结果】在所讨论的含Mg和Si元素的铝阳极中,随着Mg含量的增加,晶粒尺寸变大,Si元素对晶粒尺寸和细化有一定的影响;Mg与Zn形成的偏析相能够引发点蚀,使阳极活化性能增强。最佳阳极电化学性能的元素适宜添加量为0.09%Si,1.0%Mg。【结论】Mg元素能够影响晶粒尺寸和偏析相类型进而影响阳极的活化性能,晶粒尺寸小、晶界偏析为主的铝阳极综合性能最佳。

Correlation between Microstructure and Properties of Aluminum Alloy Sacrificial Anodes Containing Mg in the Seawater Environment

Objective] In order to solve the problem of performance degradation of sacrificial anode in deep sea environment,Mg and Si elements were added to the Al-Zn-In sacrificial anode,and the mechanism of Mg and Si on the microstructure and properties was analyzed.Methods] The influences of segregation phase and grain refinement on the properties of aluminum anode were investigated by metallographic observation and potentiodynamic polarization curve test.Results] In the Mg-containing and Si-containing aluminum anodes,as the Mg content increases,the grain size becomes larger and the Si element has a certain effect on the grain size and refinement of aluminum anodes containing Mg and Si.The segregation phase formed by Mg and Zn can initiate pitting and enhance the activation efficiency of the anode.The optimum anodic electrochemical properties of the element are suitably added in an amount of 0.09% Si,1.0% Mg.Conclusion] Mg element can affect the grain size and segregation phase type and then affect the activation performance of the anode,the aluminum anode with small grain size and more grain boundary segregation has the best comprehensive properties.