SLM-Ti仿生微纳米复合结构超疏水表面的构建

以选区激光熔化技术制备的金属钛为基体,采用阳极氧化法在SLM-Ti表面微米级球形"模板"上一步制备仿生微纳米复合结构。结果表明,未经紫外光照或高温处理的SLM-TiO_2纳米管在经全氟辛基三乙氧硅烷(1H,1H,2H,2H-perfluorooctyltriethoxysilane molecules, POTS)修饰后即获得了超疏水表面,其静态水接触角约163.8°,滚动角1°。对比分析了阳极氧化后商用纯钛CP-TiO_2和SLM-TiO_2的表面形貌特征和POTS修饰后的静态/动态水接触角。测得POTS修饰后的CP-TiO_2和SLM-TiO_2表面静态水接触角分别约为149.0°和163.8°,即二者均显现出静态超疏水特性。但在有自清洁、防水、防污特性要求时,材料表面的动态接触角才是更为重要的参数,在相同条件下获得的CP-TiO_2表面在倾斜至90°后水滴依然粘附在材料表面,而SLM-TiO_2表面水滴在倾斜不足1°时即快速地(155 ms内)从材料表面滚落。

Preparation of biomimetic superhydrophobic micro- and nanophotography on selective laser melted titanium

In this paper, the biomimetic micro- and nanotopography was fabricated in one step on the micron scale spherical "template" of SLM-Ti substrate by anodic oxidation technology. The results show that the TiO₂ nanotubes arrays on SLM-Ti substrate without UV irradiation or high-temperature treatment exhibit superhydrophilic property after being modified with 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane molecules. The morphology and static/dynamic water contact angle of POTS modified CP-TiO₂ and SLM-TiO₂ were compared and analyzed. The measured static contact angles of CP-TiO₂ and SLM-TiO₂ are ?149° and ?163.8° respectively, indicating that both of them are close to the superhydrophobic standard. However, the dynamic contact angle is the more important factor when self-cleaning, waterproof and anti-fouling characteristics are required. The results show that the water droplet was pinned on the CP-TiO₂ surface when the surface was tilted vertically, while the droplet on SLM- TiO₂ surface rolled off quickly within 155ms when the surface was tilted less than 1°.