Difference between hot galvanized layer and zinc aluminum alloy coating

- Jan 06, 2018 -

Difference between hot galvanized layer and zinc aluminum alloy coating

Hot galvanizing is usually used for steel strip or steel wire (stranded wire). In order to prevent the bottom material to continue to corrode, and to ensure the service life of the bottom material, the surface of the steel is blocked by the corrosion of the atmosphere. And zinc is more active than iron, and in the case of corrosion, the zinc layer can also be sacrificed to protect the steel matrix.


The hot-dip galvanized coating is the most widely used and most effective technology in steel corrosion prevention. In the construction industry, for all kinds of industrial and civil construction of light steel keel, building board, corrugated board, shutter door; in household appliances and light industry, for all kinds of household appliances and bottom shell; galvanized steel is widely used in light industry, electrical, automotive and construction industry. In the automobile industry, it is used for the car body, the outer shell, the inner plate, the floor and so on.


Hot galvanized Aluminum Alloy plating (coating containing 5%Al, 95%Zn, and rare earth elements) are the main advantages of plastic and better adhesion coating, corrosion resistance and deformation before and after the change, atmospheric corrosion resistance characteristics is much higher than that of conventional galvanized coating, and has good performance, can make the binding layer between the coating and the alloy to maintain long-term stability.


The protective effect of aluminum zinc plating is stronger, and the corrosion resistance is better than the galvanized product. The whole structure is made up of aluminum, iron, silicon and zinc, forming a dense four element crystal, which forms a barrier on the steel plate, thus effectively preventing the penetration of corrosion factor. Corrosion resistance comes from the protective function of the barrier layer of aluminum and the sacrificial protection of zinc. When zinc is sacrificed at the cutting edges, scratches and coating scraps, the aluminum forms an insoluble oxide layer and plays the protective function of the barrier.


As for the use of the difference, if the galvanized product can not prevent corrosion, it can be further selected aluminum zinc plating.