Fabrication of hydrophobic surface with hierarchical structure on Mg alloy and its corrosion resistance |
| |
Authors: | Jun Wang Dandan Li Xi Yin Xiaoyan Jing |
| |
Affiliation: | a College of Material Science and Chemical Engineering, Harbin Engineering University, Nantong Street 145, Harbin 150001, PR China b The Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, 150001, PR China |
| |
Abstract: | A hydrotalcite/hydromagnesite conversion coating with hierarchical structure has been fabricated on a Mg alloy substrate by in situ hydrothermal crystallization method. A MgO layer existing between the hydrotalcite/hydromagnesite film and the substrate was formed prior to the hydrotalcite/hydromagnesite film during the crystallization process. After surface treatment with silane coupling agent, the surface of conversion coating changes from hydrophilic to hydrophobic. Scanning electron microscopy (SEM) revealed that the silylated conversion coating with hierarchical structure maintains the original rough surface of which was composed of numerous micro-scale flakes and beautiful flower-like protrusions. Polarization measurements have shown that the hydrophobic conversion coating exhibited a low corrosion current density value of 0.432 μA/cm2, which means that the hydrophobic conversion coating can effectively protect Mg alloy from corrosion. Electrochemical impedance spectroscopy (EIS) showed that the impedance of the hydrophobic conversion coating was 9000 Ω. It means that the coating served as a passive layer with high charge transfer resistance. |
| |
Keywords: | Conversion coating Silylation Hydrophobicity Corrosion resistance Mg alloy |
本文献已被 ScienceDirect 等数据库收录! |