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This post was last edited by Wang Wei2 on 2020-5-27 09:56. Harsh corrosive environments cause significant damage to facilities and equipment in industries such as petroleum, metallurgy, and power generation; the direct and indirect losses resulting from corrosion are astonishing； For a long time, in the field of corrosion prevention, efforts have been made to develop coatings that provide long-term protection for the objects to be protected – namely, high-performance anti-corrosion coatings. How can the corrosion resistance life of a coating be improved? First, the coating itself possesses good resistance to corrosive agents ； Second, the coating should have good resistance to permeation by the medium ； Third, the shrinkage stress and coefficient of expansion within the coating should be low (high shrinkage stress and coefficient of expansion can cause cracks and peeling in the coating). To meet these requirements, one approach is to choose corrosion-resistant resin materials; a more important and effective measure, however, is to use high-performance anti-corrosion fillers. Glass flake, as a special anti-corrosion filler, is used in anti-corrosion coatings to endow them with the aforementioned properties. Therefore, glass flake coatings possess excellent corrosion resistance, making them a popular new type of corrosion-resistant material. Glass flake coatings have been successfully applied in China’s petroleum, metallurgy, power generation, and other industries, achieving excellent results. The characteristics of glass flake coatings are as follows: 1. Glass flake coatings can be widely used in: oil and petrochemical pipelines, storage tanks, equipment, etc ； The flue gas desulfurization equipment in metallurgical power plants can also be used as an impermeable layer for fiberglass-reinforced plastic equipment. 2. Corrosion prevention mechanism of glass flakes: Glass flakes are extremely thin pieces of glass that are produced by melting glass at a temperature of 1700°C and then blowing it using a unique process. Glass in its high-temperature molten state is processed using special techniques, which endows the glass flakes with properties such as greater strength and lower density compared to ordinary glass. Glass is an inorganic material, and its composition gives it excellent resistance to chemicals and aging. Glass scales are very thin, and when applied properly, the scale coating allows them to be arranged side by side within the coating layer, just like fish scales or layers of armor, thus forming a dense barrier against leakage. (Some people describe this structure as labyrinthine.) It is possible for there to be dozens or even hundreds of such layers, which makes it difficult for corrosive agents to penetrate the protected substrate; this prolongs the path and time taken for these agents to penetrate, thereby enhancing the coating’s resistance to penetration and its corrosion resistance over time. The large number of glass flakes in the coating create numerous small areas, which separate the microcracks and microbubbles present in the coating; this **slows down the rate of penetration of the medium, thereby significantly reducing its permeability. The resistance of glass flake coatings to medium penetration is several times to a dozen times higher than that of other materials. The presence of glass flakes not only reduces the difference in thermal expansion coefficients between the coating and the substrate, but also significantly lowers the hardening shrinkage rate of the coating itself. The hardening shrinkage rate of glass flake coatings is only a fraction to several tenths of that of other materials, which not only helps to prevent cracking and peeling of the coating but also enhances its adhesion and impact resistance. 3. Surface treatment of glass flakes: Treating glass flakes with silane-based couplers can significantly enhance the adhesion between the flakes and the resin, thereby improving the impermeability of the coating and reducing its water absorption. Moreover, the treated glass flakes have good floating properties in resin, which facilitates parallel alignment between the flakes and the matrix, thereby improving the impermeability of the coating. 4. Amount of glass flakes: The amount of glass flakes added to the coating should neither be too small nor too large; an appropriate amount will yield the best results. A lack of scales leads to overlapping arrangements between the sheets, resulting in poor impermeability of the coating ； As the amount used increases, the shielding effect grows, and the resistance to permeation improves accordingly. However, an excessive amount can hinder the proper arrangement of the scales within the coating, leading to a disordered arrangement and an increase in voids inside the coating, which in turn reduces its density. Therefore, there is an optimal range for the amount of scales, which should be between 20% and 35%. 5. Composition of glass flake coating: Glass flake coating is a highly corrosion-resistant coating composed of a corrosion-resistant resin as the main film-forming material, glass flakes as fillers, along with additives such as initiators and accelerators. 6. Glass flake coatings can be classified by viscosity into: flake coatings, thick paste-type flake coatings, and glass flake putty. Scales make up a significant proportion of scale clay, with their content generally ranging from 30% to 40%. Glass flake coatings have become increasingly important anti-corrosion coatings due to their unique properties, easy application, and strong repairability.