摘要
利用二次微弧氧化法在AZ40M镁合金表面成功制备了黑色的氧化膜层,通过SEM、EDS和XRD表征了膜层的微观形貌和成分组成。结果表明,柠檬酸铁添加剂浓度可显著影响镁合金表面氧化膜的形貌、组成和厚度,添加剂浓度越高,膜层中的铁氧化物含量也越高,而对膜层厚度的影响则没有呈现出明显规律。同时,测试了0.1 mol/L Na Cl溶液中的电化学阻抗谱和动电位极化曲线,结果显示镁合金表面黑色膜层具有较好的耐蚀性,且膜层越厚,铁含量越少,膜层的耐蚀性越好。
Black oxide films on Mg-alloy AZ40 M were prepared by means of a two-step micro-arc oxidation process in electrolytes of 15 g/L Na_3PO_4＋ 3 g/L NaF＋5.6 g/L KOH and 20 g/L Na_3PO_4＋5 g/L Na F with different additions of ferric citrate respectively. The microstructure and composition of the films were characterized by scanning electron microscope（SEM）, energy dispersive spectrometer（EDS） and X-Ray diffractometer（XRD）. The electrochemical corrosion property of the films was assessed by using electrochemical impedance spectroscopy（EIS） and potentiodynamic polarization curves in 0.1 mol/L Na Cl solution. Results showed that the concentration of ferric citrate strongly affects the surface morphology, composition and thickness of the formed oxide films. The oxide films have good corrosion resistance. The thicker oxide film with less iron content presents better corrosion resistance.
出处
《中国腐蚀与防护学报》
CAS
CSCD
北大核心
2017年第4期360-365,共6页
Journal of Chinese Society For Corrosion and Protection
基金
国家自然科学基金(21321062)~~
关键词
镁合金
微弧氧化
黑色氧化膜
腐蚀
电化学阻抗谱
magnesium alloy
micro-arc oxidation
black oxide film layer
corrosion
electrochemical impedance spectroscopy
