Study On Preparation And Properties Of Superhydrohobic Surface Of Stainless Steel

The stainless steel material with super-hydrophobic property is widely used in the modern industry. The super-hydrophobic surface has good application values in the aspects of corrosion resistance, anti-icing and self-cleaning. However, it is still a challenge to study the preparation of stable and effective stainless steel with super-hydrophobic surface.Preparation of super-hydrophobic surface of stainless steel must meet two requirements: First, the surface has a micro/nano composite morphology, which is the basis for the construction of super-hydrophobic surface; Second, the substrate surface with the composite morphology can modify the organic hydrophobic group.The commonly used methods for the preparation of super-hydrophobic surface are hydrothermal method, chemical etching,electrochemical corrosion. However, they all have certain requirements on the substrate that can cause destruction of the surface. Based on the above situation, this study provides a method for preparing super-hydrophobic surface of stainless steel with high efficiency and wide application.In this study, a highly effective method that can be widely used to prepare super hydrophobic stainless steel was examined. First, silane coupling agent KH550 was hydrolyzed, then the solution of hydrolyzed KH550 was used to modify nano silica; The modified nano silica was homogeneously dispersed in diluted aqueous acrylic coating. After the substrate surface was coated, it formed micro and nano structures. Then,the self-assembly reaction of stearic acid was carried out, and the hydrophobic long chain was formed on the surface of the substrate.The technological conditions of preparing super-hydrophobic stainless steel surface were obtained by orthogonal test: When the content of modified nano silica was 1.2%, the concentration of stearic acid solution was up to 10%, and the reaction time was 3h, the contact angle can reach up to 152.8 degrees, which formed the best hydrophobic surface. The 3 factors that affects the surface contact angle were further investigated: the number of nanoparticles, the self-assembly time, and the concentration of stearic acid solution. It was found that all these three factors affect the contact angle by changing the surface morphology.After measuring the hydrophobic surface formed, the surface free energy is reduced by 87.34%, and the rolling angle is measured to be about 10 degrees, which has a good self-cleaning ability. Also, in a certain temperature range, the anti-icing time on surface of super-hydrophobic stainless steel is nearly 65 times higher than that of the untreated surface. The electrochemical workstation was used to characterize the corrosion resistance of super-hydrophobic surfaces. The results showed that when the corrosion medium was NaCl, H2SO4,NaOH, electrode resistance of the super-hydrophobic surface was improved than that of the untreated surface, which indicates that the corrosion resistance of the super-hydrophobic surface enhanced significantly.