ZhenAn Ferro Silicon 72
In smelting ferrosilicon, coke is used as a reducing agent to make the self-baking electrode easier to carburize. Coke bricks are used to build the tap hole and the iron flow trough. Sometimes graphite powder is used to coat the ingot mold, and a carbon sample spoon is used to take liquid samples, etc. . In short, during the smelting of ferrosilicon from the reaction in the furnace until the iron is tapped, there are obviously many opportunities for contact with carbon during the pouring process. However, the carbon content of ferrosilicon is less than 0.1%, generally 0.05~0.07%. What is the reason?
Ferro Silicon Aluminum
Research shows that the solubility curve of carbon in ferrosilicon at 1187°C shows that the higher the silicon content in ferrosilicon, the lower the carbon content. According to data, when the silicon content in ferrosilicon is greater than about 30%, most of the carbon in ferrosilicon exists in the state of silicon carbide (SiC). Silicon carbide is easily oxidized and reduced by silicon dioxide or silicon monoxide in the crucible. Silicon carbide has very little solubility in ferrosilicon, especially when the temperature is low, and it is easy to precipitate and float. Therefore, the silicon carbide remaining in ferrosilicon is very low, so the carbon content of ferrosilicon is very low.
Ferro Silicon
The carbon content in ferrosilicon needs to be controlled, because carbon easily reacts with oxygen to produce carbon monoxide, which easily creates bubbles in the molten steel and affects the quality of the steel. Of course, when producing ferrosilicon, the carbon content itself is relatively low.
