The reason why the coated steel plate is not easy to be corroded is mainly due to the following reasons:
1. Anti-rust coating: A layer of anti-rust coating is applied to the coated steel plate during the manufacturing process, usually by hot-dip galvanizing or spraying on the surface of the steel plate. This coating can form a physical barrier to prevent air, moisture and corrosive substances from reaching the surface of the steel plate, thereby reducing the corrosion rate of the steel plate.
2. Metal coating: hot-dip galvanizing is a commonly used anti-corrosion treatment method for coated steel sheets. During hot-dip galvanizing, steel sheets are dipped in molten zinc to form a layer of zinc. Zinc has the property of self-corrosion. When the surface of the steel plate is damaged, the zinc layer will preferentially corrode, which plays a role in protecting the steel plate from corrosion.
3. Coating layer protection: The coating layer in the coated steel plate also plays a role in protecting the steel plate. The coating layer usually has good corrosion resistance and can prevent water, oxygen and other corrosive media from corroding the steel plate. The coating layer can be a variety of materials such as organic coating, phosphate layer, aluminum-zinc alloy layer, etc.
4. Properties of steel itself: steel itself is usually composed of iron and some alloying elements, and has high strength and corrosion resistance. The zinc layer formed during the galvanizing process can provide additional protection and make the steel plate have better corrosion resistance.
It should be noted that the corrosion performance of coated steel plates still has certain limitations, especially in the case of long-term exposure to harsh environments or serious scratches and damages, corrosion may still occur. Therefore, it is still necessary to pay attention to the protection of the coated steel plate in use and maintenance.
