Preparation And Properties Of Organic Modified Inorganic Corrosion Resistant Coating

In recent years, with the development of technology, the requirements to materials and components are increasingly demanding. High-performance corrosion-resistant inorganic coatings are widely used in the protection of metal surfaces. The main component of the traditional inorganic coating material is oxide, however the coating’s chemical bond type is monotonous, hard and brittle, and the stain-resistant ability is poor, the same as alkali resistant ability. Organically modified inorganic coatings prepared by Sol-gel has several advantages, such as low synthesis temperature, small particle size and the wide applicability.Tetraethoxysilane (TEOS) and tetrabutyl titanate (TBT) are used as a precursor in this work, y-acryloyloxygentrimethoxysilane (KH570) as organic modifier as well. By means of sol-gel method, compact and solid organic-inorganic hybrid films were prepared on45steel, and by scanning electron microscopy (SEM), infrared absorption spectroscopy (FT-IR) test used to study the morpHology and structure of the modified coating. Salt bath corrosion and polarization curve are applied to characterize the corrosion resistance of the coatings. We systematically studied the influence of the precursor molar ratio of SiO2system and the heat treatment temperature on the coating structure and properties. The results show that when the R value is4, pH is4, and the heat treatment temperature is180℃, the best precursor ratio is1. In optimum conditions, the optimum heat treatment temperature is180℃, Modified SiO2coating can provide good mechanical shielding effect. As to the TiO2system, the optimal preparation condition is that R value is2, PH is4, and the heat treatment temperature is300℃, the best precursor ratio is1. When the coating samples were exposed by ultraviolet light source, the anti-corrosion effect of the coating may be raised, indicating that the phtocatalytic reaction has been arosed in the TiO2matrix. So the matrix provides both mechanical protection and cathodic protection. The overall anti-corrosion effect of TiO2system is superior to the SiO2system.