海水环境中典型阴离子对5083铝合金腐蚀行为的影响  

Influences of Typical Anions in Seawater Environments on Corrosion Behaviors of 5083 Aluminum Alloy

作　　者：涂扬帆 冯立明[1] 方志刚[3] 刘海涛[2] 井明华 管勇[3,2] 

机构地区：[1]山东建筑大学材料科学与工程学院,山东济南250101 [2]中国科学院金属研究所,辽宁沈阳110016 [3]海军装备研究院,北京100161

出　　处：《电化学》2017年第4期466-472,共7页Journal of Electrochemistry

基　　金：国家自然科学基金项目(No.51201169)资助

摘　　要：采用析因分析试验及动电位极化曲线、电化学阻抗谱(EIS)等测试方法,研究了海水环境因素中的典型阴离子(Cl^-、HCO_3^-、SO_4^(2-))交互作用对5083铝合金耐蚀性的影响.结果表明,三种阴离子中,Cl^-、HCO_3^-对铝合金点蚀起促进作用.Cl^-与HCO_3^-交互作用时,在Cl^-浓度一定的情况下,随着HCO_3^-浓度的增加,5083铝合金耐蚀性呈现出上升→下降→再上升的趋势,在70~90 mg·L^(-1)时耐蚀性能明显降低;在HCO_3^-浓度一定的情况下,Cl^-浓度较低时5083铝合金耐蚀性比Cl^-浓度较高时差.在Cl^-、HCO_3^-浓度较低情况下,SO_4^(2-)具有抑制腐蚀的作用;当Cl^-、HCO_3^-浓度较高时,SO_4^(2-)抑制腐蚀的作用不明显.The interaction effects of typical anions, namely, CI-, HCO; and SO4：, presented in seawater environments on corro sion resistance behaviors of AA5083 aluminum alloy have been studied. The corrosion resistances of the 5083 aluminum alloy in different simulated seawater environments were tested by factorial analysis method. The polarization curves, the corrosion poten- tials, corrosion current densities and the breakdown potentials were examined in different concentrations of Cl^-, HCO3^- and SO4^2-. The corrosion behavior was analyzed by electrochemical impedance spectroscopy （EIS）. The results showed that both Cl^- and HCO3^- could accelerate the pitting corrosion. When the concentration of CI remained constant, the corrosion resistance of AA5083 aluminum alloy increased initially with an increase in the concentration of HCO3^-, and then dropped dramatically at 70 - 90 mg. Ll, which displayed the best corrosion resistance performance. Afterwards, the corrosion resistance increased again. The corrosion current density of AA5083 aluminum alloy was not significantly affected by SO4^2- when the concentrations of Cl^- and HCO3^- became larger. Meanwhile, when the concentration of HCO3^- was fixed, the charge-transfer resistance of AA5083 aluminum alloy at a lower Cl^- concentration was smaller than that at a higher CI concentration, and the corrosive ions could easily penetrate the native oxide film by a redox reaction with the matrix.

关 键 词：5083铝合金 耐蚀性 电解质效应 海水环境 

分 类 号：TG178[金属学及工艺—金属表面处理]