Self-repairing functionality and corrosion resistance of in-situ Mg-Al LDH film on Al-alloyed AZ31 surface  

作　　者：Yi-Xing Zhu Guang-Ling Song Peng-Peng Wu 

机构地区：[1]Center for Marine Materials Corrosion and Protection,College of Materials,Xiamen University,422 S.Siming Rd,Xiamen,Fujian 361005,China [2]State Key Laboratory of Physical Chemistry of Solid Surfaces,Xiamen University,422 S.Siming Rd,Xiamen,Fujian 361005,China [3]School of Mechanical and Mining Engineering,The University of Queensland,Brisbane,Queensland 4072,Australia

出　　处：《Journal of Magnesium and Alloys》2023年第5期1567-1579,共13页镁合金学报（英文）

基　　金：The research is supported by the National Science Foundation of China(key project grant No.51731008 and general project grant No.51671163).

摘　　要：A novel Mg-Al LDH film was in-situ prepared hydrothermally in an alkaline aqueous solution on an Al-alloyed AZ31 substrate.The structural,chemical and functional characteristics of the film were explored by means of scanning electron microscope(SEM),X-ray diffraction(XRD),energy dispersive spectrometer(EDS),polarization curve,AC impedance and salt immersion tests,respectively.The anti-corrosion results indicated that the Mg-Al LDH film on the Al-alloyed AZ31 surface could effectively protect the AZ31 from corrosion attack even after 90 days of immersion in 3.5 wt.%NaCl solution.The protection performance is surprisingly better than most of the reported coatings on Mg alloys.More interestingly,when the Mg-Al LDH film was scratched,the exposed Al-alloyed surface might gradually release metal ions and re-generate dense LDH nano-sheets in the corrosive environment to inhibit the further corrosion there,exhibiting a self-repairing behavior.The combination of the benign long-term protection and desirable self-repairing performance in this new process of surface-alloying and LDH-formation may significantly extend the practical application of magnesium alloys.

关 键 词：LDH film Surface alloying Corrosion resistance SELF-REPAIRING 

分 类 号：TG174.4[金属学及工艺—金属表面处理]