Description
Hot-dip Galvalume Steel Coil (GL) is a high-end anti-corrosion basic steel product with a standard alloy coating ratio of 55% aluminum, 43.4% zinc and 1.6% silicon. The alloy layer is deeply fused with the steel substrate through high-temperature hot-dip technology, with strong adhesion, avoiding falling off, peeling and cracking. The finished surface presents uniform and delicate silver natural star spangles with high-grade texture, flat and clean surface without missing plating, black spots, burrs and oxidation defects, making it the preferred substrate for high-end industrial manufacturing and construction engineering.
It integrates the anti-oxidation and high-temperature resistance of aluminum and the sacrificial anode anti-corrosion advantage of zinc, with performance far exceeding traditional hot-dip galvanized steel. Aluminum forms a dense and stable alumina protective film on the steel surface to isolate air, water vapor, acid and alkali media from the substrate and inhibit oxidation and corrosion fundamentally. When the sheet has cut sections or scratch damage, the zinc alloy layer will undergo sacrificial reaction to protect the internal steel substrate preferentially and prevent corrosion diffusion. Its salt spray resistance and corrosion resistance are 2-4 times that of ordinary galvanized steel, especially prominent in humid, coastal and chemical harsh environments.
It also has excellent high-temperature resistance, working stably under 300℃ high temperature for a long time without discoloration, delamination and oxidation under short-term high-temperature baking. It features excellent processing performance, adapting to bending, stamping, cutting, welding and roll forming without coating falling off and cracking after processing. Multiple surface treatments are available: conventional passivation, chrome-free environmental protection passivation, oiling and anti-fingerprint treatment, meeting different downstream processing and usage requirements and global environmental protection standards.
As a core basic substrate, it is mainly used as the special substrate for PPGI and PPGL color coated steel. It can also be used directly in bare state, widely applied in building roof and wall panels, ventilation and smoke exhaust ducts, high-temperature equipment shells, oven and fireplace housings, photovoltaic brackets, agricultural machinery, electrical equipment back panels, outdoor metal components and hardware products.
