expanded mild steel mesh

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 zinc reaches saturation in the solid melt, the two elements of zinc and iron atoms diffuse 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 iron, while the iron diffused into the molten zinc liquid forms an intermetallic compound FeZn13 with zinc and sinks into the bottom of the hot-dip 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%.

Cold galvanized by electrolytic action to metal and other materials surface attached to a layer of metal film, so that the surface of the material uniform texture, anti-corrosion wear, appearance is more beautiful. Hot dip galvanized coating is thicker, generally 30-60 microns, coating corrosion resistance is higher. Suitable for outdoor work of steel parts, such as highway fences, power towers, large size fasteners and other “rough” workpiece long-term rust prevention.