The Construction of Superhydrophobic Structure on Stainless Steel by an Optimized Chemical Etching Technics

Abstract

Austenitic stainless steel is a widely used engineering material in industry and daily life due to its excellent corrosion resistance. The construction of superhydrophobic structure on stainless steel can endow it with special wetting properties and open up new paths for its application. In this study, stainless steel plate was first etched in a hydrofluoric acid solution with a low concentration of 40 wt%, and a micro-nano structure was obtained in a short time of 2 h. The surface was then modified in myristic acid to achieve superhydrophobicity. The superhydrophobic structure on the steel showed a high contact angle (CA) of 166 deg, excellent self-cleaning performance, and greatly improved corrosion resistance compared with the original counterpart. Meanwhile, its wear durability was evaluated by sandpaper abrasion test and the superhydrophobic structure maintained its property after moving 125 cm on the 1000-grit sandpaper under a pressure of 3.2 kPa.