摘要
In situ-grown Mg-Al layered double hydroxide(LDH)films were obtained on an anodized AZ31 substrate,with the immersion of sample in different concentrations of Al^(3+)solution.The structure,composition and morphology of LDH films were investigated by X-ray diffraction(XRD),Fourier transform infrared(FTIR)and scanning electronic microscopy(SEM),and the corrosion behavior of LDH films was further studied by electrochemical impedance spectroscopy(EIS).The influence of Al^(3+)concentration on the growth behavior of LDH was also discussed.The results indicated that the nest-like structure of MgAl-LDH film was composed of interconnected MgAl-LDH nanosheets.Besides,the LDH obtained in0.032 mol·L^(-1)Al^(3+)solution,possessing dense laminated structure,could effectively seal the porous surface of anodic oxide film.EIS results revealed that the samples coated with LDH films showed a higher electrochemical impedance,and thus,the corrosion resistance of samples coated with LDH films was signally improved compared with the anodized alloy.
基金
supported by the National Key Research and Development Program of China(2016YFB0301100)
the National Natural Science Foundation of China(51701029,51531002,51474043)
China Postdoctoral Science Foundation Funded Project(2017M620410,2018T110942)
the ChongqingPostdoctoral Scientific Research Foundation(Xm2017010)
the Chongqing Research Program of Basic Research and Frontier Technology(cstc2016jcyjA0388,cstc2017jcyjBX0040)。
