The zinc content of the plating bath in the hot-dip galvanized sheet zinc pot is not less than 99%, which is the more economical type of corrosion-resistant coating at this stage. Pure zinc-coated thick steel plates are divided into two types: non-zinc flower and zinc flower. Their corrosion resistance is basically the same. If you need to spray or paint afterward, products without zinc flowers will be more beautiful; while products with thick zinc layers are generally dominated by flowers (for example, the weight of the zinc layer is 273g/m2 on both sides). It is said that Posco of Japan sells to the Chinese market The entrance and exit are hot-dip pure galvanized steel guardrail rolls with a zinc layer of 600g. However, because the thick zinc layer affects the welding assembly line, the cost is not as high as the overall immersion plating of the parts, and the pure zinc coating is not suitable for the cut surface of the thick steel plate. Maintenance wasn't that great either, so sales in China weren't great.
Aluminum zinc coating
The plating solution contains about 55% aluminum, about 1.6% silicon, and the remaining component is zinc. The corrosion resistance of aluminum-zinc coating is higher than that of pure zinc coating in most environments. All aluminum-zinc coated coil steel is There are zinc flowers. Excellent steel mills can produce well-proportioned and beautiful zinc flowers, and the power supply products can be used directly, but the aluminum-zinc coating also has some defects. The welding performance of aluminum-zinc coated steel plates is not as good as that of pure zinc, especially when using a resistance welder, the molten coating metal will stick to the top of the electrode. Since the strength of the metal material to be bonded after melting is relatively high, the use of ordinary sharpening tools to remove the metal is very inefficient and will cause the level head to be charged. Therefore, welding methods should be avoided as much as possible during use. In addition, the protective effect of aluminum-zinc coating on steel plate broken openings is far inferior to that of pure zinc coating (and far inferior to zinc-aluminum-magnesium coating). It is necessary to do a good job in corrosion resistance of broken openings (such as Paint closed).
