mono coil ppgi coils jiangsu colour grain coated galvanized ppgi steel coils1

Hot dip aluminum coating is another commonly used metal coating. Due to the easy formation of a very dense layer of aluminum oxide on the surface of aluminum, it has extremely excellent atmospheric corrosion resistance, which is more than twice that of hot-dip galvanized layers under the same conditions. Although the standard electrode potential of aluminum (-1.66 volts) is lower than that of iron (-0.44 volts) and zinc (-0.76 volts), the oxide film is very stable and can act as an isolation film. In 1954, the American Steel Company experimented with the lifespan of aluminum plated steel plates as roof panels in the southern United States. After 23 years of continuous use, it has been proven that aluminum plated steel plates have a corrosion resistance of about 5-9 times that of hot-dip galvanized steel plates in industrial, marine, and rural environments. Aluminum plated steel plates also have excellent resistance to sulfide corrosion, and their resistance to sulfide corrosion is many times stronger than galvanized steel plates.