Category: hot dip galvanized steel coil factory
By Alisajpq, 2019-03-26
The advantage of hot-dip galvanized coil is that it has a long anti-corrosion life and has always been a popular environmentally-friendly anti-corrosion treatment. What are the advantages of hot-dip galvanized coil? The following is the principle of hot-dip galvanized coil. The following low cost hot dip galvanized steel coil factory has introduced the following points and hope to help you.
Hot-dip galvanized coil, also called hot dip galvanizing, is a method in which a steel member is obtained by immersing in molten zinc to obtain a metal coating. With the rapid development of high-voltage transmission, transportation and communication, the requirements for steel protection are getting higher and higher, and the demand for hot-dip galvanized coils is also growing.
Usually, the thickness of the galvanized layer is 5 to 15 μm, and the galvanized layer is usually 35 μm or more, or even as high as 200 μm. The hot-dip galvanized coil has good coverage, and the coating is dense and free of organic inclusions. It is well known that the mechanism of zinc against atmospheric corrosion includes mechanical protection and electrochemical protection. Under atmospheric corrosion conditions, ZnO, Zn(OH)2 and alkaline zinc carbonate protective films on the surface of the zinc layer slow down the corrosion of zinc to a certain extent. This protective film (also known as white rust) is damaged. A new film layer will be formed.
When the zinc layer is severely damaged and endangers the iron matrix, zinc electrochemically protects the substrate. The standard potential is zinc-0.76V and the standard potential is iron-0.44V. When zinc and iron form micropores, zinc dissolves as an anode and iron acts as a cathode. Obviously, hot-dip galvanized coils have better atmospheric corrosion resistance to bismuth metal iron than electrogalvanized steel sheets.