摘要
采用高速电火花线切割加工方法与电刷镀工艺结合在铝合金表面构筑了类水稻叶多尺度层级结构表面.利用扫描电子显微镜(SEM)、激光共聚焦显微镜(LSCM)、X射线衍射仪(XRD)和接触角测量仪表征表面的形貌结构、物相组成和润湿特性.结果表明,电刷镀获得的双尺度(微-纳米)微观结构对表面疏水性起关键作用,而高速电火花线切割加工获得的规则排列亚毫米级槽棱结构进一步放大了其平槽方向表面的疏水性能,使其未经任何化学修饰即获得优异的超疏水特性,接触角可以达到151°,且展现平槽和垂槽方向不同的疏水特性.这一研究将对各向异性功能材料结合超疏水材料的应用起到一定的指导意义.
With the continuous exploration of the special morphologies and properties of skin of some animals and plant leaf surfaces in the nature, new hydrophobic surfaces are developed through imitation of the observed surface effects. The aluminum alloy surface which is similar to multi-scale hierarchical structure surface of biomimetic rice leaf can be obtained by combining high speed wire electrical discharge machining (WEDM) method and eleclric brush-plating technique. The morphological feature was analyzed by scanning electron microscopy (SEM). The surface wettability of the sample was measured at ambient temperature using a contact angle measurement instrument and the SCA20 software by placing a 4 pL pure distilled water droplet onto the surface of the sample. Three dimensional (3D) profile of the sample surface was obtained through confocal laser scanning microscopy (LSCM). The elemental composition was determined by X-ray diffraction (XRD) analysis in order to determine the phase composition on the sample surface. The regular submiIIimeter groove ridge structures were processed on the aluminum alloy surfaces by the method of high speed wire electrical discharge machining. And the hierarchical cauliflower-like structures which were consisted of micro-protrusions and submicro-grains were formed on the sample surfaces by electric brush-plating technique. The anisotropic fianctional surfaces and the superhydrophobic surfaces were achieved by the combination of the regular submillimeter groove ridge structures and hierarchical cauliflower-like structures. The research showed that the regular submillimeter groove ridge structures are similar to the surface morphology on rice leaf, and the hierarchical cauliflower-like structures are similar to the surface morphology on lotus leaf. The results showed that double scale (micro-submicro) microscopic structure obtained by electric brush-plating can play a key role on the hydrophobicity of the surface. The regular submillimeter groove ridge structure
出处
《科学通报》
EI
CAS
CSCD
北大核心
2017年第16期1766-1773,共8页
Chinese Science Bulletin
基金
国家自然科学基金(51505039)
吉林省科技发展计划(20150204018GX)
中国博士后科学基金(2014M551145)资助
关键词
超疏水
多尺度
各向异性
类水稻叶
superhydrophobic, multi-scale, anisotropy, biomimetic rice leaf