An intermediate poly-dopamine layer for alginate coating on high-purity magnesium to achieve corrosion mitigation  

作　　者：Qingyun Fu Weihong Jin Mingcheng Feng Jingyao Li Jian Li Wei Li Zhentao Yu 

机构地区：[1]Institute of Advanced Wear&Corrosion Resistant and Functional Materials,Jinan University,Guangzhou 510632,China [2]Northwest Institute for Nonferrous Metal Research,Xi’an 710055,China

出　　处：《Journal of Magnesium and Alloys》2023年第6期2061-2071,共11页镁合金学报（英文）

基　　金：financially supported by National Key Research and Development Project of China(No.2020YFC1107202);Shanxi Provincial Key Research and Development Project(No.2019ZDLSF03–06);Guangdong Basic and Applied Basic Research Foundation(No.2020B1515120078);Science and Technology Planning Project of Guangdong Province(No.2021A0505030042)。

摘　　要：Although magnesium(Mg)and its alloys are proposed as the next generation orthopedics transplanted materials,their clinical applications are limited by the fast degradation.To reduce the degradation rate,a strong adhesion poly-dopamine(PDA)layer was introduced as an intermediate layer for the subsequent alginate(ALG)spin-coating on high-purity Mg.The surface morphology and chemical composition were detected by scanning electron microscope,energy disperse spectroscopy,and Fourier transform infrared spectroscopy.The corrosion resistances of all samples were evaluated by electrochemical and 10-day immersion tests in Hanks’balanced salt solution.Our results suggest that the thickness of the fabricated PDA/ALG composite coating is 8.58±0.65μm,and the intermediate PDA layer evidently enhances the adhesion between the substrate and ALG coating.The corrosion current density of Mg coated with the PDA/ALG composite coating decreases more than 10 times compared to that of the Mg substrate,and the charge transfer resistance is 12 times bigger than that of the bare Mg,which indicates the improved corrosion resistance.Moreover,the mechanism of corrosion protection of the composite coating is also discussed.

关 键 词：MAGNESIUM COATING Ploy-dopamine ALGINATE CORROSION 

分 类 号：TG174.4[金属学及工艺—金属表面处理]