Weather-resistant steel (weathering steel) generally adopts the process routes of concentrate feeding into furnace-smelting (converter, electric furnace-micro alloying treatment-argon blowing-LF refining-low superheat continuous casting (feeding rare earth wire) -controlled rolling and controlled cooling. During smelting, scrap steel is added into the furnace together with the charge and smelted according to the conventional process. After tapping, the deoxidizer and alloy are added. After the molten steel is treated by argon blowing, it is immediately cast. Slab.
Due to the addition of rare earth elements in the steel, the weathering steel is purified and the content of inclusions is greatly reduced. (Rare earth elements are extremely active elements and are strong deoxidizers and desulfurizers. They mainly purify steel. Rare earth elements can refine grains, change the state of inclusions in steel, reduce the number of harmful inclusions, and reduce Source of corrosion, thereby improving the resistance of steel to atmospheric corrosion)
Different weather resistance elements have different corrosion effects in different environments. For example, molybdenum is effective in reducing the corrosion rate of the industrial atmosphere, but the corrosion resistance of the marine atmosphere is not obvious. Therefore, depending on the corrosion environment, the weathering steel is specific and special. With the development of use, the composition system has also changed accordingly to improve the effectiveness and application efficiency of the addition of weather-resistant elements.
Special steel grades such as seawater corrosion-resistant steel, marine weather-resistant steel, acid-resistant weather-resistant steel, and heat-resistant climate-resistant steel are representative of this type of steel. Therefore, weathering steel should also be diversified.