The difference between galvanized sheet and galvalume steel coil is mainly the difference in coating. The surface of galvanized sheet is evenly distributed with a layer of zinc material, which acts as an anodic protection for the base material, that is to say, the alternative corrosion protection of zinc material. In addition to the use of the base material, the base material inside can only be damaged when the zinc is completely corroded.
The surface coating of the aluminized zinc coil is composed of 55% aluminum, 43.5% zinc and a small amount of other elements. The surface of the aluminized zinc coating is a honeycomb structure under the microscopic view, and the "honeycomb" made of aluminum contains zinc. In this case, although the aluminum-zinc coating also plays the role of anode protection, on the one hand, due to the reduction of zinc content, on the other hand, the zinc material is wrapped in aluminum and is not easy to electrolyze, so the role of anode protection is greatly reduced. Therefore, once aluminum is plated The zinc plate is cut, and it will rust soon when the cut edge is basically lost and protected. Therefore, the aluminum-zinc plate should be cut as little as possible. Once cut, the edge can be protected by applying anti-rust paint or zinc-rich paint. The service life of the plate is prolonged.
