MB8镁合金表面超疏水复合膜层的制备与表征

Preparation and Characterization of Superhydrophobic Duplex-treated Film on Surface of MB8 Magnesium Alloy

利用微弧氧化技术在镁合金表面制备微米级粗糙结构,采用环氧树脂溶液和纳米二氧化硅分散液对该表面进行涂覆处理,得到二氧化硅纳米颗粒均匀分布的粗糙表面,再利用全氟硅烷改性,制备得到具有超疏水性的复合膜层。采用扫描电镜、X射线衍射仪、接触角测量仪、高速摄影系统评价膜层的形貌结构和润湿性。结果表明,微弧氧化层所具有的微米级结构和纳米二氧化硅颗粒组成的微/纳二元粗糙结构对疏水性的提高具有重要作用;复合膜层表面的接触角随二氧化硅分散液浓度的提高呈现先增加后减小趋势,并最终逐渐稳定在150o左右;在二氧化硅分散液浓度为10.0g/L时,复合表面的接触角最大,可达161o,在此条件下获取的复合表面对不同pH值的液滴均具有超疏水性。同时该表面对水滴呈现低黏附特性。

Micron scale rough structures of MB8 magnesium alloy substrate were acquired by micro-arc oxidation technique. Nanoscale rough structures on the surface of micro-arc oxidation coating were prepared by painting Epoxy acetone solutione and silica suspension subsquently. Superhydrophobic duplex-treated film was fabricated by perfluorodeeyltrichlorosilane self-assembled monolayers deposited on micro- and nanostructures. Scanning electron microscope, X-ray diffractometer, contact angle measurement and high-speed camera system were used to analyse the surface properties and the wettability of specimens. The results indicate that micro- and nano-structures by micro-arc oxidation and nano-silica play an important role in preparing superhydrophobic surface. The contact angles on duplex-treated film increase initially and then reduce with increasing of concentration of silica suspension, and finally stabilize at around 150° gradually. The maximum contact angle of 161° is acquired when concentration of silica suspension is 10.0 g/L. The duplex-treated film acquired under this condition shows superhydrophobicity to water droplets with different pH values. The films also possess the characteristics of low adhesion.