Weathering steel refers to the addition of a small amount of alloy elements (such as copper, phosphorus, chromium, molybdenum, titanium, niobium, vanadium, etc.) to carbon steel to form a dense protective film on the steel surface. It has a stable and dense rust layer, which can prevent the rust from penetrating further into the interior without the need for surface coating, which is the so-called "rust made of rust" steel. Compared with carbon steel, this type of steel has good resistance to atmospheric corrosion.
Low-alloy high-weather-resistant steel, that is, atmospheric corrosion-resistant steel, is a new type of steel that has been popularized and applied in China in recent years. It is widely used in railway vehicles, train cars, various weather-resistant building structural parts, towers, and bridge auxiliary structural parts.
High weather resistance low alloy structural steel products include hot rolled steel plates, cold rolled steel plates and section steel. Usually used in the delivery state, it can make bolted, riveted and welded structural parts. The thickness of steel used for welding structure is generally not more than 16mm.
The standard of high weather resistance structural steel is GB / T4171-2008. The main grades are 09CnPCrNi-A, 09CuPCrNi-B, 09CuP, 09CuPTiRE and so on.