Comparison of corrosion resistance between color-coated sheet and color-coated steel sheet

Color-coated sheet refers to a pre-coated metallurgical product made by continuous coating of protective and decorative organic coatings or films on the surface of steel or aluminum strips. Internationally, it is collectively referred to as pre-coated coils. It is mainly composed of three parts: metal substrate, chemical conversion film and organic coating. The organic coating can be formulated into various colors, and can be made into various patterns by means of printing and embossing technology, so it can replace the traditional paint decoration. This kind of steel plate combines the properties of both organic polymers and metals, and has good corrosion resistance and processing and forming properties. The manifestation of the corrosion resistance of color-coated boards is usually expressed by the degree of corrosion damage such as loss of gloss, discoloration, chalking, fine cracking, cracking, bubbling and rust spots on the surface of the coating. There are many factors that affect the corrosion resistance of color-coated boards, which involve the types of substrates and coating thicknesses of color-coated boards, coating types and coating levels and thicknesses, environmental conditions of use, and mechanical processing, transportation, and application of color-coated boards. Storage, construction and installation and post-construction maintenance and many other factors. However, from the analysis of the coating characteristics of the color-coated board, the fundamental factors that determine the corrosion resistance of the color-coated board are the structural characteristics of the coating and the corrosion resistance of the substrate; the protection of the coating in the atmospheric corrosion environment is mainly determined by Weathering or aging resistance of coatings.