Galvalume ( aluminium&zinc-silicate coated ) steel, based upon the cold-rolled steel coil and produced through continuous zinc hot coated technical process by using 55% aluminium, 43% zinc and 2% silicate. The coating layer is Zn-Ai alloy.Because of the good feature of corrosion resistance, the galvalume steel is 2 to 6 times as high as zinc coated in terms of air corrosion resistance of building materials,electric appliance,auto and house hold appliance,etc.