A Study Of Defrosting And Anti-Icing Behavior On Super-Hydrophobic Aluminum Surfaces

Micro-Nanostructure was prepared via chemical etching on aluminum surface. After fluorination treating, the aluminum surface exhibits super-hydrophobic properties with a water contact angles of 161.3°. The surface was observed with scanning electron microscope. It is found that the surface is configured in a labyrinthic structure with plateaus and caves of Micro-Nanostructure. In addition, aluminum surfaces of different water contact angles were prepared according to changing the time of chemical etching.In the sub-cooling environments, frosty experiment was carried out on the aluminum surface using humidifier to supply the small water droplets. According to the comparison of the quantity of frost formed on the super-hydrophobic, hydrophobic and common aluminum surfaces at different temperature and time, the effect in resisting frost of super-hydrophobic aluminum surface was studied. And actual frosty phenomenon on super-hydrophobic aluminum surface was discussed. In addition, effects of different water contact angles on frosty status on aluminum surfaces were investigated. The result shows that the bigger the water contact angle is, the less the quantity of frost.Effects of super-hydrophobic aluminum surface on frozen status were also studied. According to the comparison of the frozen quantity on the super-hydrophobic, hydrophobic and common aluminum surfaces and on surfaces of different water contact angles at different temperature and time, the effect in resisting ice of super-hydrophobic aluminum surface was investigated. It is shown that the frozen quantity is least on super-hydrophobic aluminum surface. And as time prolonged and the temperature dropped, the growth of the quantity of ice is also slowest on super-hydrophobic aluminum surface. Besides, the bigger the water contact angle is, the less the quantity of ice. In addition, effects of the height between the point of water dripped and super-hydrophobic aluminum surface on the quantity of ice were discussed. The result shows that the quantity of ice is increasing with the height increasing when the temperature is not enough low because of the wallop of water to surface enhanced with the height increasing. However, ice appears at lower height with the temperature decreasing.