Silicon-manganese alloy is mainly used as an intermediate material for deoxidation and alloying in steel production, and it is also the main raw material for the production of medium and low carbon manganese iron. 

Silicon-manganese alloy is an alloy composed of manganese, silicon, iron and a small amount of carbon and other elements. It is a widely used and high-yield iron alloy. Its consumption accounts for the second largest among electric furnace iron alloys. The silicon and manganese in the silicon-manganese alloy have a stronger affinity for oxygen. When used in steelmaking, the deoxidation products produced by silicon-manganese alloy, MnSiO3 and MnSiO4, have melting points of 1270℃ and 1327℃ respectively, featuring low melting points, large particles, easy floating, and good deoxidation effect. Under the same conditions, using manganese or silicon alone for deoxidation results in burn-off rates of 46% and 37% respectively, while using silicon-manganese alloy for deoxidation, the burn-off rate is 29%. Therefore, it has been widely applied in steelmaking, with its production growth rate higher than the average growth rate of iron alloys, and has become an indispensable composite deoxidizer and alloying agent in the steel industry. Silicon-manganese alloys with carbon content below 1.9% are also used as semi-finished products for producing low-carbon manganese iron and electrolytic metal manganese in the production process. In iron alloy production enterprises, the silicon-manganese alloy used in steelmaking is usually called commercial silicon-manganese alloy, the silicon-manganese alloy used for smelting low-carbon iron is called self-use silicon-manganese alloy, and the silicon-manganese alloy used for smelting metals is called high-silicon silicon-manganese alloy. Manganese can form silicides with silicon such as MnSiO3, MnSiO, and MnSiO3. From the silicon-manganese phase diagram, it can be seen that the most stable silicide is MnSi. Due to the negative value of the formation free energy of manganese's silicide, it is much greater than the negative value of the formation free energy of manganese's carbide, and the higher the silicon content in the silicon-manganese alloy, the lower the carbon content.