The coating of steel substrate is the most commonly used method, and also the best one among various methods. Galvanization has greatly increased the corrosion resistance of steel, and also increased the sales of hot-dip galvanized square tubes, hot-dip galvanized angle steel and other products.
Because the process temperature of hot galvanizing is relatively high, it is easy to anneal the materials with lower tempering temperature in the process of galvanizing, thus reducing the hardness. In addition, the effect of the thickness of the coating on the fit tolerance should also be considered when using hot galvanizing for the fit parts.
Hot galvanizing is to immerse the derusted steel members in the molten zinc molten at about 600 ℃ to make the surface of the steel members adhere to a zinc layer. The thickness of the zinc layer shall not be less than 65 for the thin plates below 5mm μ m. No less than 86 for thick plate μ m。 So as to prevent corrosion. In recent years, a large number of profiled steel plates in light steel structural systems have emerged. Hot galvanizing is also widely used for corrosion protection. The first process of hot galvanizing is pickling and rust removal, followed by cleaning. The incompleteness of these two processes will leave hidden dangers for corrosion prevention, so they must be treated thoroughly.
