Hot Dip Galvanized Channel Steel
Principle of Galvanized Channel Steel Hot-dip galvanized layer is formed by three steps of zinc in high temperature liquid state:
1. The surface of the iron base is dissolved by the zinc liquid to form a zinc-iron alloy phase layer;
2. The zinc ions in the alloy layer further diffuse to the substrate to form a zinc-iron mutual dissolving layer;
3. The surface of the alloy layer is surrounded by a zinc layer.
(1) It has a thick and dense pure zinc layer covering the surface of the steel, which can avoid the contact of the steel substrate with any corrosive solution and protect the steel substrate from corrosion. In the general atmosphere, a very thin and dense zinc oxide layer is formed on the surface of the zinc layer, which is difficult to dissolve in water, so it has a certain protective effect on the steel substrate. If zinc oxide and other components in the atmosphere form insoluble zinc salts, the corrosion protection effect is more ideal.
(2) With iron-zinc alloy layer, combined with compactness, it exhibits unique corrosion resistance in marine salt spray atmosphere and industrial atmosphere;
(3) Because of the firm bonding, zinc-iron is mutually soluble, and has strong wear resistance;
(4) Because zinc has good ductility, and its alloy layer adheres firmly to the steel base, hot-dipped parts can be formed by cold punching, rolling, wire drawing, and bending without damaging the coating;
