What is the anti-corrosion function of anti-corrosion equipment?

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The anti-corrosion effect of anti-corrosion equipment usually exists simultaneously, and its anti-corrosion mechanisms include the following three aspects: physical, chemical, and electrochemical. ⑴Physical anti-corrosion effect. By appropriately combining pigments that react with oily film-forming agents, a dense anti-corrosion coating can be obtained, thereby enhancing the physical anti-corrosion effect. For example, lead-containing pigments react with oils to form lead soaps, which make the anti-corrosion coating more dense and thereby reduce the penetration of harmful substances such as water and oxygen. Phosphate pigments, upon hydrolysis, form insoluble basic salts that act to block pores in anti-corrosion coatings. Iron oxides, or pigment fillers such as flaky mica powder, aluminum powder, and glass flakes, can all reduce the permeability of anti-corrosion coatings, providing physical protection against corrosion. ⑵Chemical preservative effect. When harmful acidic or alkaline substances penetrate the anti-corrosion coating, it can neutralize them and turn them into harmless substances; this is also an effective anti-corrosion method. In particular, by cleverly using amphoteric compounds such as zinc oxide, aluminum hydroxide, and barium hydroxide, it is possible to easily neutralize acidic or alkaline harmful substances to exert a preservative effect, or to react with water and acids to produce alkaline substances. These alkaline substances adsorb on the surface of steel, keeping it alkaline; in an alkaline environment, steel is less prone to rusting. ⑶Electrochemical corrosion inhibition. The moisture and oxygen that penetrate through the pores in the coating react with the preservative agents dispersed within the coating as it passes through, thereby forming preservative ions. This moisture containing preservative ions reaches the metal surface, causing the steel surface to become passivated and preventing the release of iron ions; chromate pigments possess this property. Alternatively, metals with an electrode potential lower than that of steel can be used to protect steel; for example, zinc-rich coatings function as sacrificial anodes because zinc has a lower electrode potential than steel, which prevents the steel from corroding easily.