Study on Preparation and Corrosion Resistance of Fluorine Free Copper Based Superhydrophobic Surface

Abstract

Corrosion failure is the bottleneck for restricting the application and development of copper-based metal materials. As a new technology of improving corrosion resistance, superhydrophobic surface provides an effective way to solve the problem of copper corrosion. In this work, the superhydrophobic copper surface was prepared by wire electrical discharge machining (WEDM) and surface modification with stearic acid. Subsequently, scanning electron microscope was used to observe the surface micro morphology, video optical contact angle meter was used to measure the wettability, and the corrosion behavior was further tested through the electrochemical workstation. Results showed that the micron strip nano stalactite graded composite structure on the copper surface had been successfully prepared, and the surface of the composite structure exihibited excellent superhydrophobic properties. In addition, compared with the substrate, the corrosion resistance of the prepared surface was increased by 99.35%. The corrosion prevention mechanism of the superhydrophobic surface was systematically studied and analyzed, and it was found that the formation of micro nano composite structure could effectively capture air to form a solid gas liquid interface on the surface of the sample, and the existence of the air layer further impeded the electron transfer and material transfer rate between the substrate and the electrolyte. Thereby, the electrochemical corrosion rate of the substrate was inhibited, and the corrosion resistance of the superhydrophobic copper sample was significantly improved. Overall, the method was simple, efficient and widely used, and the preparation process was environmentally friendly, which could be applied to large-scale production.

Keywords

• copper metal|superhydrophobic surface|wedm|corrosion resistance