1. Basic concept and principle of silane ceramic treatment technology
Silanized technology is a new nano metal pretreatment technology, which is phosphorus free and free of any harmful metals, and provides superior corrosion resistance for a wide range of metal substrates. It can completely replace the traditional iron, zinc and ternary phosphating products, and is environmentally friendly. First of all, the rare earth salt in the working fluid forms a dense and uniform inorganic deposit layer rich in - OH group on the surface of metal substrate under the coordination of various auxiliary components. Then, the hydrolyzed silane molecules form hydrogen bond with me oh group on the metal surface (where me is metal) through Si OH group, and quickly adsorb on the metal surface. In the subsequent drying process, Si OH group and me oh group further agglomerated, and si-o-me covalent bond was formed on the interface. On the other hand, the remaining silane molecules form a Si-O-Si three-dimensional network structure on the metal surface through the condensation reaction between Si OH groups. Therefore, a layer of dense, interpenetrating, cross-linked network structure membrane is formed on the surface of the silane treated substrate.

After zinc or ternary phosphating treatment, the surface of the metal is gray white to dark gray, and the surface is slightly rough. According to different materials, the appearance of the metal surface after silanized treatment is generally divided into yellow to blue (cold rolled plate), reflective brown to blue (galvanized plate), luminous gray (aluminum plate), and no coarse sense.