The surface of hot-dip galvanized aluminum alloy coating plate is flat, silver-gray, with metallic luster, and the surface is uniformly distributed al-Zn alloy crystal. The surface layer of the coating is solid dendritic crystal, the dendrite part is aluminium-rich phase solid solution, and the dendrite part is zinc-rich pseudo-eutectic phase. The inner layer is al-Fe-Si-Zn intermetallic compound layer, and the structure of the coating determines its quality characteristics as follows:

1) Due to the combination of the non-dynamic protection of aluminum and the sacrificial anode protection of zinc, the remarkable performance of hot-dip galvanized aluminum alloy coating plate (GL) is characterized by excellent corrosion resistance. The corrosion resistance of hot-dip aluminum-zinc alloy coating plate is 2 ~ 6 times that of hot-dip galvanized zinc alloy plate. In addition, GL plates exhibit excellent notch resistance in the middle and later stages of use.

2) Due to the high melting point of aluminum and strong resistance to oxidation and thermal reflection, GL plate has excellent high-temperature corrosion resistance performance. GL plate is allowed for long-term use at 300℃ working environment and short-term use at 500 ~ 600℃ high temperature environment. The working environment temperature of GI is generally allowed to be room temperature only, and the limit working temperature is 230℃.

3) The GL plate has a flat surface, silver gray and metallic luster, and the surface is evenly distributed al-Zn alloy crystal, so it has a good decorative appearance.

4) As the porosity of the al-Zn alloy coating is at least 2%, GL plate is prone to corrosion in the process of inventory and transportation, resulting in white rust, black spots and other defects. In addition, GL also has good coating, molding and welding performance, which can meet the requirements of users in construction, household appliances and automobile industries.