Fabrication of bionic superhydrophobic surface on X52 pipeline steel

Abstract

A superhydrophobic surface was prepared successfully on X52 pipeline steel surface using the sandblasting roughening treatment, chemical etching and fluorination treatment composite methods. The pipeline steel surface was modified with(heptadecafluoro-1,1,2, 2-tetradecyl)trimethoxysilane(HFTTMS). The effects of HCl concentration and the chemical etching time on the morphology of the pipeline steel surface and the wettability of the surface with distilled water were researched. The results show that at certain HCl concentration, with the increase of the chemical etching time, the contact angles increased and had a maximum value. When the chemical etching time was too long, the pipeline steel surface reacted with HCl for too long, and the complexity of surface microstructure decreased, resulting in the decrease of the contact angle. With the increase of HCl concentration, the reaction between the pipeline steel surface and HCl became severe, the surface morphology became more complex, and the fractal dimension increased. When HCl concentration was too high, the surface fine projection structures were etched off, resulting in the decreases in the complexity and the fractal dimension of the surface structures. Therefore, the contact angle decreased. The sample sandblasted for 1.5 min and etched chemically for 1.5 h at 7 mol/L HCl can obtain the best surface fine structure. After the fluorination treatment, the biggest contact angle is 156.4°.