Introduction to Galvanized Aluminum-Magnesium Steel Sheet

TIME：

2021-10-26

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Industry News

The coating of zinc–aluminum–magnesium–nickel–rare earth alloy‑coated steel sheet is formed by the high‑temperature solidification of zinc (Zn), aluminum (Al), and magnesium (Mg). Its microstructure consists of a dense ternary eutectic phase comprising Zn, Al, and Zn2Mg, thereby creating on the surface of thick steel sheets a highly compact, natural barrier that effectively prevents the penetration of corrosive agents. Compared with conventional galvanized steel sheets, its superior performance is notably reflected in four key aspects.

The coating of zinc–aluminum–magnesium–nickel–rare earth alloy‑coated steel sheets is formed by the high‑temperature solidification of zinc (Zn), aluminum (Al), and magnesium (Mg). Its microstructure consists of a dense ternary eutectic phase comprising Zn, Al, and Zn2Mg, thereby creating on the surface of thick steel plates a highly compact, natural barrier that effectively prevents the penetration of corrosive agents. Compared with conventional galvanized steel sheets, its superior performance is notably reflected in four key aspects.

1. Ultra-corrosion-resistant:

Aluminum–magnesium–zinc alloy coating is incorporated into the hot‑dip galvanized steel sheet, with additional alloying elements such as aluminum, magnesium, and silicon. This further enhances the coating’s corrosion‑inhibiting performance. Compared with conventional hot‑dip galvanized products, it achieves superior corrosion resistance despite a lower coating adhesion, offering 10–20 times the corrosion resistance of standard hot‑dip galvanized steel.

2. Self-healing property

Near the cut surface, the coating composition undergoes continuous homogenization, forming a dense protective film primarily composed of zinc hydroxide, basic zinc chloride, and aluminum hydride. This protective film exhibits low electrical conductivity and effectively inhibits corrosion of the cut surface.

3. Long lifespan

Due to its exceptional corrosion resistance—10 to 20 times that of conventional hot-dip galvanized steel—and its self‑healing capability at cut edges, prefabricated components made from hot‑dip zinc‑aluminum‑magnesium alloy‑coated steel exhibit a significantly longer service life, typically exceeding 30 years.

4. Easy to manufacture and process:

The coating of hot‑dip galvanized aluminum‑magnesium steel is denser than that of conventional galvanized steel; consequently, it is less prone to coating delamination during stamping operations. It exhibits excellent formability under challenging conditions, making it well suited for drawing, deep drawing, sheet‑metal bending, and welding processes. Moreover, owing to the high strength of its coating, it offers exceptional resistance to mechanical damage.