Research on a reversible superwetting behavior and its corrosion resistance

A simple, efficient and low-cost method is proposed to prepare surfaces with reversible superwettability and excellent corrosion resistance. Superhydrophobic surfaces are successfully obtained on the copper alloys by etching, heat treatment, and then stearic acid modification, exhibiting extraordinary water repellence with a static contact angle of 159.7 +/- 1.2 degrees, and a sliding angle of 3.1 +/- 0.6 degrees. The reversible transition of the superwetting state are successfully achieved. The surface can be turned into a superhydrophilic state by simple heat treatment. And then, it can be turned into a superhydrophobic state by re-modification. Meanwhile, the effects of etching time and heat treatment temperature on wettability are also studied. Finally, the corrosion resistance of the copper alloys and the durability under various extreme conditions are investigated. The results show that the prepared superhydrophobic copper alloys have excellent corrosion resistance with a corrosion inhibition rate of 98.83% and superior durability, which will further expand its practical applications.