Timing and methods of adding ferrosilicon in the steelmaking process
As we all know ferrosilicon is an essential ferroalloy for smelting steel, ferrosilicon is a ferroalloy made by smelting silica and iron oxide, so when is ferrosilicon added in the steel making process? The following by the ferrosilicon manufacturers to answer your questions.
In the smelting of silicon steel or spring steel and heat-resistant steel, a large number of ferrosilicon needs to be added for alloying, the added ferrosilicon must be baked red for a long time. The main reason is that ferrosilicon contains more hydrogen, baked red can be removed, and preheating ferrosilicon can also accelerate melting; in addition, because ferrosilicon is lighter, a large number of joining the furnace, there is bound to be part of the silicon and slag deoxidation, the generation of acidic products silica, reducing the local slag alkalinity, so the quality of steel is not good. In order to prevent this situation, before and after the addition of ferrosilicon to add the right amount of lime, in order to maintain the alkalinity of the slag, and send electricity with a large voltage for a few minutes, so that the slag melts and reacts well, becoming a uniform white slag. The recovery rate of ferrosilicon is between 90%- 98%.
In refining, when the chemical composition is adjusted, the temperature is appropriate and the slag is good, this is when ferrosilicon can be added. After addition the steel comes out within 10-25min. If the time is too short, ferrosilicon is too late to melt completely, and silicon is not evenly distributed in the steel. If the time is too long, it is easy for the steel to absorb gas and affect the quality of the steel.
