基于分形理论的疏水功能表面润湿性分析

Analysis on Wettability of Hydrophobic Functional Surface Based on Fractal Theory

为分析疏水功能表面的形貌参数对其润湿性的影响,以1060铝合金为基体材料,通过化学刻蚀预处理,电解刻蚀和硬脂酸修饰相结合的方法,制备疏水功能表面。通过调控化学刻蚀时间,使表面具有不同的微观形貌,进而改变其润湿性。利用扫描电子显微镜对疏水功能表面的微观形貌进行表征,利用接触角测量仪对其润湿性进行测定。基于图像处理技术,对疏水功能表面的微观形貌特征信息进行提取与分析。结果表明,同一表面在不同的放大倍数下,其灰度值分布统计具有相似的规律,说明所制备的疏水功能表面具备分形特征;利用差分盒子维数算法对表面维数进行计算,不同化学刻蚀时间所对应的表面维数与其润湿性的变化规律相吻合,说明维数是疏水功能表面的润湿性调控参数之一。

To analyze the effect of the morphology of hydrophobic functional surface on the wettability, a hydrophobic functional surface was prepared by chemical etching pretreatment, combination of electrolytic etching and stearic acid modification based on 1060 aluminum alloy. The prepared surface had different micro-morphologies and its wettability was changed by regulating the chemical etching time. The micro-morphology of the surface was characterized by scanning electron microscopy and the wettability of the surface was investigated by contact angle meter. The micro-morphology information of the surface was extracted and analyzed based on image processing technology. The results show that the gray distribution of the surface is similar in different magnification, which indicates that the surface has fractal characteristics. The surface dimension is calculated by the differential box-counting algorithm, the surface dimensions corresponding to different chemical etching times are consistent with the change rule of the wettability, indicating that the dimension is one of the wettability control parameters of the hydrophobic functional surface.