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galvalume steel)Because the steel plate will produce oxidation corrosion when it is wet, an anti-corrosion protective layer must be added on the surface. Generally, the anti-corrosion coating is divided into hot-dip galvanized Zn and hot-dip aluminum zinc alloy Al Zn (the components of aluminum zinc alloy are aluminum 55%, zinc 43.5% and silicon 1.5%, referred to as 55% Al Zn). The data show that the comprehensive anti-corrosion capacity of 55% aluminum zinc plating is 4 times that of zinc plating with the same thickness.
(galvalume steel)The base material anti-corrosion coating of general profiled steel plate (pit plate) shall not be less than 350g / ㎡ (Z35) hot-dip galvanizing or 185g / ㎡ (az185) hot-dip aluminum galvanizing
(galvalume steel)As the minimum hot-dip galvanized layer of cold-rolled section steel and floor slab of building structure, the specification of zinc / galvanizing is 275 g / ㎡ (z27), and the requirement of coastal exposed parts is 350g / ㎡ (Z35).