摘要
采用扫描电化学显微镜(SECM)中的极化曲线法和交流阻抗图谱法研究5083铝镁合金在不同浓度NaCl溶液中的腐蚀行为,结果表明:合金在中性NaCl溶液中的腐蚀为钝化材料体系,随着盐度的增加,Cl^-对合金基体的破坏加剧,腐蚀电位正移,点蚀电位减小,其电化学阻抗谱中仅有1个容抗弧且呈现收缩趋势.同时,阻抗减小,相位角增加,弥散指数降低,合金的耐腐蚀性能下降.溶液中存在强活化作用的Cl-,会损坏合金表面的氧化膜,逐渐取代腐蚀产物Al(OH)_3中的OH^-,生成新的腐蚀产物AlCl_3.
The corrosion behavior of 5083 aluminum magnesium alloy in NaCl solution at different concentrations was studied by polarization curve method and AC impedance spectroscopy in scanning electrochemical microscopy(SECM).The results show that the corrosion of alloy is neutralized in neutral NaCl solution.With the increase of salinity,the damage of Cl-to the alloy matrix is aggravated.The corrosion potential is positive and the pitting potential is decreased.The electrochemical impedance spectroscopy is only 1 capacitive arc,showing a contraction trend.At the same time,the impedance decreases,the phase angle increases,the dispersion index decreases,and the corrosion resistance of the alloy decreases.The strong activation of Cl-in the solution,will damage the alloy surface oxide film,gradually replacing the OH-in corrosion products of Al(OH)3 and formation of new corrosion products of AlCl3.
作者
杨少华
张丹城
田亚斌
叶昌美
赵宇娟
李林山
YANG Shaohua;ZHANG Dancheng;TIAN Yabin;YE Changmei;ZHAO Yujuan;LI Linshan(School of Metallurgical and Chemical Engineering,Jiangxi University of Science and Technology,Ganzhou 341000,China;Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100090,China)
出处
《有色金属科学与工程》
CAS
2018年第2期1-5,共5页
Nonferrous Metals Science and Engineering
基金
国家自然科学基金资助项目(51664022)
关键词
5083铝镁合金
扫描电化学显微镜
极化曲线
交流阻抗
腐蚀
5083 aluminum magnesium alloy
scanning electrochemical microscopy
polarization curve
AC impedance
corrosion
