采用电化学蚀刻方法在碳化硅颗粒增强复合材料(Si C/Al)表面构筑了微纳结构,重点分析了蚀刻电流密度和蚀刻时间等关键操作参数对所得表面微观形貌及润湿特性的影响。研究发现,较高电流密度(6 A/dm2)下刻蚀的Si C/Al复合材料表面可形成由微米级"粒状"结构和纳米级结构(颗粒状和波鳞状)复合而成的微–纳双层结构,且这种特殊结构不因后续刻蚀时间延长而改变;优化条件形成的Si C/Al复合材料刻蚀表面呈现出静态接触角高达160.7?、滚动角低至4?的超疏水特性。本研究结果说明Si C/Al复合材料可用于制备自清洁表面。
Micro- and nano-structures were prepared based on Si C particulate reinforced composite substrate using electrochemical etching process, and effects of current density and etching time on morphology characteristics and superhydrophobicity of the etched surfaces were investigated. The results show that a special hierarchical structure consisting of particle-shaped microstructures and nano-structrues(particle- or squama-shaped) is formed on the etched Si C/Al composite at the current density of 6 A/dm2, which keeps almost unchanged during etching period. Under optimized process conditions, superhydrophobic surface can be obtained, achieving a water contact angle of up to 160.7° and an extremely small tilting angle of 4°. All these data demonstrate that Si C/Al composite has potential to be used as self-cleaning surface.