In today's architectural design, more and more houses use the steel for the frame structure.General construction of high-rise buildings and large public buildings, stadiums, pavilion,theater, etc. are steel structure. While the corrosion of steel structure seriously restricts the
development and application of steel structure, so the steel rust prevention becomes more critical and important nowdays.
1. The Use of Weathering Steel
Based on the electrochemical principle of steel corrosion, we can prevent the corrosion of steel by preventing or destroying the formation of the corrosion cell or strong block to cathode and anode process.Applying protective layer to prevent steel corrosion is the common method, which mainly including;
The corrosion resistance which is superior to the general steel structure called weathering steel. It usually contains phosphorus, copper, nickel, chromium, titanium metal, forming the metal surface protective layer, in order to improve corrosion resistance.The low temperature impact toughness are better than the common structure of the steel. 2. The Steel Hot-dip Zinc Processing
Hot dip zinc is to put the steel in the melting zinc liquid(high to 600 ℃) ,making the zinc layer adhered on the surface of the steel, which realizes the purpose of corrosion protection. 3.Spraying Aluminum Composite Coating (zinc) on The Steel
This is long-lasting corrosion protection methods whose effect is equal to hot-dip zinc corrosion. The detailed process is to blast sand on the surface of steel components, making its surface with metallic luster and roughened. Then acetylene-oxygen flame melt aluminum(zinc) wire, and blowing with compressed air attached to the surface of steel components, to form a honeycomb of aluminum (zinc) coating layer (thickness between 80μm ~ 100μm).Finally, fill with epoxy resin or neoprene paint and other coatings pores,to form a composite coating. 4.Anti-corrosion Coating
Anti-corrosion coating of steel components may be employed in different ways depending on the circumstances, such as a metal protective layer (galvanized), paint coatings, composite protective layer.At present the usual practice is to brush a layer of anti-corrosion coating.Coating is a kind of colloidal solution with oil or not.Coating on the steel surface, it can form a layer to protect the steel
structure.Anticorrosive coatings generally consists of primers and paint. 5.Cathodic protection
Attach active metal on the surface of steel structure instead of steel corrosion,which is the ususal solution for underwater and underground structure.The approach is to use more active metal or coated as electrochemical reaction, to protect steel.The advantage of this approach including less construction time and perfect antiseptic effect.
It is reported that PTH mainly use aluminum plating zinc, galvanized and painting ways on anti-corrosion of steel structure and material processing.For example, Ction veneer of substrate applies aluminum zinc plating processing, aluminum zinc high to 100 g/m⊃2;, the thickness of PE surface reaches 25 um. C type light steel keel adopts aluminized zinc processing, aluminum zinc high to 100 g/m⊃2;. As to the C/Z type cold bending thin-wall steel, PTH applies hot dip galvanize on the surface, and the galvanized quantity reaches 275 g/㎡, which is high standard in the industry.