The effect of anodization process on oxidation film with micro-nanoporous structure on the surface of SUS430 stainless steel prepared in an electrolyte consisting of ammonium fluoride, water, and ethylene glycol (Eg) was studied by scanning electron microscopy (SEM). The compositions of the interior micropore and the nonporous position of the anodized film were analyzed using energy-dispersive spectrometer (EDS). The water contact angles of the stainless steel surface before and after anodizing were measured. Suitable reduction of water content in electrolyte is beneficial increasing the density of micropores and the optimal concentration of NH4F for forming micro-nanoporous structure is 0.15 mol/L. Too high anodizing voltage and too long anodizing time result in excessive corrosion of the oxidation film. The microporous structure with a pore diameter of 3-5μm where orderly nanopores with a honeycomb-like structure and ca.100 nm in diameter are formed inside can be prepared on the surface of stainless steel under the following conditions: NH4F 0.15 mol/L, water <0.4 mol/L, electrolyte temperature 20 °C, anodizing voltage 50-60 V, and time 15-30 min. Oxide and fluoride are formed on the surface of stainless steel after anodizing. The oxidation film has a contact angle of 138.2° to water, showing good hydrophobicity.%利用扫描电镜(SEM)研究了阳极氧化工艺对 SUS430不锈钢在由氟化铵、水及乙二醇(Eg)组成的电解液中制备微纳多孔结构氧化膜的影响,通过能谱仪(EDS)对阳极氧化膜微孔内部和未成孔位置的组成进行了分析,测试了阳极氧化前后不锈钢表面的水接触角。适当降低电解液含水量有利于提高不锈钢表面的微孔密度,可形成微纳多孔结构的氟化铵浓度以0.15 mol/L最好,氧化电压过大以及氧化时间过长都会导致阳极氧化膜发生过度腐蚀。在氟化铵含量为0.15 mol/L、含水量小于0.4 mol/L的电解液中,保持电解液温度为20°C,采用氧化电压50~60 V阳极氧化15~30 min,不锈钢表面可制备出孔径为3~5μm的多孔结构,微米级孔洞内部形成有序的蜂窝状纳米多孔结构(孔径约为100 nm)。阳极氧化后不锈钢表面形成了氧化物和氟化物,与水的接触角为138.2°,具有较好的疏水性。
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