The formation process of hot dip galvanized layer is the process of forming iron-zinc alloy between the iron matrix and the outside pure zinc layer. The surface of the workpiece forms the iron-zinc alloy layer during the hot dip plating, so that the iron and pure zinc layer is well combined. The process of large roll galvanized wire can be simply described as: when the iron workpiece is immersed in the molten zinc solution, the first zinc and α-iron (body-centered) solid melt is formed on the interface. This is a crystal formed by the matrix metal iron dissolved with zinc atoms in the solid state. The two metal atoms are fused with each other, and the gravitational attraction between the atoms is relatively small.
Therefore, when the zinc reaches saturation in the solid melt, the two elements of zinc and iron atoms are diffused with each other, and the zinc atoms diffused into (or infiltrated into) the iron matrix migrate in the lattice of the matrix and gradually form an alloy with the iron, while the iron diffused into the molten zinc liquid forms an intermetallic compound FeZn13 with the zinc and sinks into the bottom of the hot galvanized pot, that is, zinc slag. When the workpiece is removed from the zinc leaching solution, the surface of the pure zinc layer is formed, which is hexagonal crystal, and its iron content is not more than 0.003%.
Hot dip galvanizing, also known as hot dip galvanizing, is a method of obtaining a metal covering by immersing a steel member in a molten zinc solution. With the rapid development of high-voltage transmission, transportation and communication, the protection requirements for steel parts are becoming higher and higher, and the demand for hot-dip galvanizing is also increasing. Usually the thickness of electric galvanized layer is 5 ~ 15μm, and the large roll galvanized wire layer is generally more than 35μm, even up to 200μm. Hot dip galvanizing has good covering ability, dense coating and no organic inclusions.
Post time: 19-12-22