Investigation of Super-Hydrophobic Coatings with Hierarchical Structures Surface on Mild Steel

Abstract

A hierarchical roughness surface with micro-and nano-structures was fabricated on mild steel by chemical etching with a mixture acid (2%HNO3 + 6%H2SO4 + 6%H3PO3) solution. The surface was modified by fluoroalkylsilane. The wettability of the modified surfaces was studied by contact angle method and Electrochemical Impedance Spectroscopy (EIS), and their morphology was investigated by Scanning Electron Microscopy (SEM). The roughness of the steel etched consisted of fine micro-steps in grains. The treated surface exhibited super-hydrophobic properties, water contact angle is high to 152° after modification for 6 min at room temperature. The results indicated that with the increase of etching time, the hierarchical structure gradually formed on the surface and the contact angle gradually decreased.

Hybrid contact and interfacial adhesion on well-defined periodic hierarchical pillars

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The Polymerization and Performance of Fluorinated Acrylic Copolymer with Low Surface Energy

“…All men-made structures submerged in seawater will suffer from the unwanted growth of bacteria, algae and invertebrates known as biofouling. Which can cause the speed drop and the more fuel consumption of ship, and lead to an extra financial burdens as well as contamination of the environment [1] . What's more, the corrosion caused by biofouling could increase the fatalness destroyed by wave attack.…”