Effect of phosphate-based sealing treatment on the corrosion performance of a PEO coated AZ91D mg alloy  

作　　者：Kun Qian Weizhou Li Xiaopeng Lu Xinxin Han Yong Jin Tao Zhang Fuhui Wang 

机构地区：[1]School of Resources,Environment and Materials,Guangxi University,Nanning 530004,China [2]Guangxi Key Laboratory of Processing Non-ferrous Metals and Features Materials,Guangxi University,Nanning 530004,China [3]Shenyang National Laboratory for Materials Science,Northeastern University,3-11 Wenhua Road,Shenyang 110819,China [4]School of Materials Science and Engineering,Northeastern University,Shenyang 110819,China

出　　处：《Journal of Magnesium and Alloys》2020年第4期1328-1340,共13页镁合金学报（英文）

基　　金：the National Natural Science Foundation of China(No.U1737102,51531007,51371059);Young Elite Scientists Sponsorship Program by CAST(2017QNRC001);Guangxi Natural Science Foundation of China(Nos.2016GXNSFDA380022);Major Science and Technology Projects in Guangxi(No.AA18118030 and AA17204100);Project of Development of Science and Technology of Nanning(No.20181191-2);the Fundamental Research Funds for the Central Universities(N170203006).

摘　　要：This study investigated the effect of sealing treatment on the corrosion performance of plasma electrolytic oxidation(PEO)coated AZ91D Mg alloy with and without addition of corrosion inhibitor.The microstructure,phase composition and corrosion property of the sealed and unsealed coatings were evaluated by using scanning electron microscopy(SEM),energy dispersion spectroscopy(EDS),x-ray diffraction(XRD),x-ray photoelectron spectroscopy(XPS),polarization,and electrochemical impedance spectroscopy(EIS)tests.Electrochemical experiments and salt spray tests showed that,after sealing in phosphate solution containing corrosion inhibitor,the corrosion current density of PEO-coated AZ91D decreased more than 10-fold and the anti-corrosion time in a salt spray environment increased more than three-fold.The corrosion rate of the PEO coating slowed down due to the releasing and adsorbing of the corrosion inhibitors in the pores and cracks of the coating during the corrosion process.

关 键 词：AZ91D magnesium alloy:Plasma electrolyte oxidation Sealing treatment Corrosion inhibitor 

分 类 号：TG174.4[金属学及工艺—金属表面处理]