铝合金表面制备超疏水复合膜层及性能评价

Preparation and properties evaluation of superhydrophobic composite film on surface of aluminum alloy

用阳极氧化工艺在铝合金表面构筑粗糙结构,喷涂改性TiO2颗粒溶胶固化后形成超疏水复合膜层。表征复合膜层的表面形貌和成分,测试静态接触角、结合力和电化学阻抗谱评价复合膜层的润湿性能、稳定性、抗污染性和耐蚀性能。结果表明:复合膜层与铝合金基体结合紧密,主要成分为Al、O、Ti、Si和C,表面呈超疏水状,静态接触角达151.2°,可有效阻挡液态污染物黏附及腐蚀介质的渗透和侵蚀,表现出良好的抗污染和耐蚀性能。复合膜层具有微纳米分级结构和低表面能,能俘获空气滞留形成一层气膜,减少与液态污染物和腐蚀介质的接触面积,从而较持久的抑制铝合金基体腐蚀且不易被污染。

A rough structure was constructed on the surface of aluminum alloy by anodic oxidation process,and then the modified sol was sprayed and cured to form a superhydrophobic composite film. The surface morphology and components of the composite film were characterized,the surface wettability,stability,antifouling property and corrosion resistance of the composite film were evaluated by measuring static contact angle,bonding force and electrochemical impedance spectroscopy. The results show that the composite film is mainly composed of Al,O,Ti,Si and C elements and closely combined with the aluminum alloy substrate. The surface is superhydrophobic and the static contact angle reaches 151.2°,which can effectively block the adhesion of liquid pollutants and the penetration and erosion of corrosive media. It indicates that the composite film has good antifouling property and corrosion resistance. The composite film has a micro-nano hierarchical structure and low surface energy,which can trap air and form a gas film to reduce the contact area with liquid pollutants and corrosive media,thereby inhibit the corrosion of aluminum alloy substrate for a long time and make it difficult to be polluted.