What is the process of deoxidizing carbon steel?

This is a requirement of the casting process, just like in steelmaking, for deoxidization. Reactions that reduce the oxygen content in steel during steelmaking and casting processes. It is an important process step in ensuring the quality of steel ingots (billets) and steel products. In molten steel, oxygen exists in the form of dissolved substances () or as non-metallic inclusions (MxOy). During oxygen-blown steelmaking, as the impurity content decreases, its content in the molten steel increases. If the deoxygenated steel melt is poured out of the furnace, the oxygen dissolved in the steel will react with carbon during the cooling process, resulting in the formation of CO bubbles and boiling ； The properties of the evolved gas vary significantly depending on the degree of deoxygenation. The fully deoxygenated molten steel does not exhibit CO precipitation during the cooling process, it does not boil, and remains calm; hence it is called killed steel ； In slightly deoxygenated molten steel, carbon reacts with oxygen during the cooling process, resulting in the formation of CO; this leads to significant boiling, and such steel is known as boiling steel ； In partially deoxygenated molten steel, after it has solidified for a while, the remaining oxygen reacts with carbon, causing brief boiling; this results in semi-killed steel. Figure 1 shows the range of oxygen content in steels with different degrees of deoxidation. As can be seen from Figure 1, deoxidation of boiling steel, that is, mild deoxidation, only results in a slight decrease in the oxygen content in the steel melt; however, this level remains above what is required for equilibrium with carbon. Semi-killed steel deoxidation, or partial deoxidation, roughly brings the oxygen content in the steel to a level that is in balance with the carbon content; hence it is also known as balanced steel. Deoxidation of calm steel involves thorough deoxidization to reduce the oxygen content in the steel to **a level below that which is in equilibrium with carbon. Although steel liquid deoxidation reduces the content of certain elements, if the deoxidation products MxOy are not allowed to rise to the surface and be removed, they remain in the steel liquid and form non-metallic inclusions in the steel, thereby affecting its quality ； Therefore, during deoxygenation, the deoxygenation products should be removed as much as possible. Therefore, deoxidation is the process of reducing the total oxygen content in steel, denoted as ∑O (where ∑O = +OMxOy). However, no matter how steelmaking technology develops and improves, inclusions always remain in the steel. Therefore, during deoxidation, it is also necessary to control the shape, size, and distribution of residual inclusions in order to ensure the various properties of the steel (see non-metallic inclusions in steel).