The Theory Of Silicon Manganese Alloy

The smelting of silicon manganese alloy in an electric furnace is the same as the smelting of carbon ferromanganese. The Fe and P in the charge are first reduced, and the high-valent oxide of Mn is decomposed in the upper layer or reduced by CO to low-valent oxide MnO. The low-valent oxide MnO then reacts with C to form carbides. The reaction formula can be written as
MnO+(1+x)C→MnCx+CO
As the charge sinks into the high-temperature zone, the reaction of C reducing SiO2 begins to occur
SiO2+2C=Si+2CO
The reduced Si then reacts with the generated MnCx to form silicon-manganese alloy and promotes the reduction of Si. The reaction formula is
SiO2+2C+MnCx=Mn·Si·Cx+2CO
The more Si is generated, the more thoroughly the carbides are destroyed, and the lower the carbon content of the alloy. When the silicon content of the alloy is less than 23.5% (such as SiMn 10, SiMn 14, SiMn 17 and SiMn 20), the reaction of silicon destroying carbides can be written as
(Mn, Fe)7C3+7Si=7(Mn ·Fe)Si+3C
If the silicon content is higher, the reaction of destroying carbides can be written as
(Mn, Fe)7C3+10Si=7(Mn·Fe)Si+3SiC