Facile Fabrication of Durable Superhydrophobic Aluminum Alloy Surfaces by HS-WEDM and Chemical Modification

Durable superhydrophobic aluminum alloy surfaces were prepared through a facile method: combining high-speed wire electrical discharge machining and chemical modification. Three types of pulse width were selected to machine the aluminum alloy surfaces with different levels of surface roughness. The effect of immersion time in perfluorooctanoic acid on the wettability of the aluminum alloy surfaces was examined. The contact angle of the superhydrophobic aluminum alloy surfaces was 159.7 +/- 3 degrees, and the sliding angle was 1 +/- 0.5 degrees. After sanding with coarse sandpaper, the aluminum alloy surfaces still exhibited superhydrophobicity with a stroke of 450 cm, indicating good mechanical durability. The prepared superhydrophobic aluminum alloy surface heated for 2h within the 190-240 degrees C temperature range showed favorable thermal stability. In addition, the superhydrophobic aluminum alloy surface exhibited self-cleaning property. Therefore, the superhydrophobic aluminum alloy surface prepared by using the simple mass production method showed good mechanical stability, thermal stability, and self-cleaning property, as well as broad application potential.