Chrome-free samarium-based protective coatings for magnesium alloys
The microstructure of chrome-free samarium-based conversion coating on magnesium alloy was investigated and the corrosion resistance was evaluated as well. The micro-morphology, transverse section, crystal structure and composition of the coating were observed by scanning electron microscopy (SEM), X-ray diffraction (XRD) , energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS), respectively. The corrosion resistance was evaluated by potentiodynamic polarization curve and electrochemical impedance spectroscopy (EIS). The results reveal that the morphology of samarium conversion coating is of crack-mud structure. Tiny cracks distribute in the compact coating deposited by samarium oxides. XRD, EDS and XPS results characterize that the coating is made of amorphous and trivalent-samarium oxides. The potentiodynamic polarization curve, EIS and OCP indicate that the samarium conversion coating can improve the corrosion resistance of magnesium alloys.
microstructure corrosion samarium conversion coating morphology
Xuming Zhang Xiufang Cui Guo Jin Yuyun Yang Lili Lin Haidou Wang Binshi Xu
School of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, National Key Laboratory for Remanufacturing, Armored Forces Engineering Institute, Beijing 100072, C
国际会议
北京
英文
660-663
2012-10-23（万方平台首次上网日期，不代表论文的发表时间）