What is high carbon ferromanganese?
Ferromanganese (high carbon), a manganese-containing ferroalloy, is made by heating a mixture of MnO2 and Fe2O3 oxides, with carbon, usually in the form of coal, in a blast furnace or electric arc furnace system, called a submerged arc. Furnaces produce ferromanganese by carbothermal reduction in furnaces. High-carbon ferromanganese is used as an oxidizer and alloying agent for steel.
Manganese is obtained from manganese ore in the form of ferromanganese, ferromanganese is used in steelmaking to provide oxygen, neutralize the negative effect of hot sulfur during hot rolling, increase the depth of hardness and increase wear resistance, tensile steel and replace nickel metal in stainless steels. will be The main factor for hot cracking of steel is the formation of an acetic compound (Fe-FeS) with a melting point of 988 degrees Celsius. By adding ferromanganese, this compound turns into MnS plastic with a melting point of 1650 degrees Celsius.
Applications of high-carbon ferromanganese
Manganese also helps to increase the fluidity of slag. The composition of steel is added to 13% of manganese (Hadfield steel). Manganese reduces the tendency to hot fracture caused by sulfur and thus hot work is done on the metal.
In the case of low manganese in steel, sulfide phase is formed. As a result, it melts during rolling and eventually causes part failure by creating cracks. By adding a certain amount of manganese, a stronger combination is created between the particles.
Application of ferromanganese, increasing hardness and strength, increasing high strength, reducing brittleness, heating steels, stabilizing austenite phase, preventing melt oxidation and increasing steel hardness.
Manganese is intentionally present in most steel grades and is a residual component of almost all other steels. Aside from its historical importance as a desulfurizer and oxidizer, manganese is undoubtedly the most common alloying agent in steels, after carbon. Therefore, it is understandable that ferromanganese is the most widely used ferroalloy.
Among the 15 steelmaking manganese products recognized in ASTM standards, the most important of them is ferromanganese with high carbon (standard). It is generally sold in two concentrations of manganese: 74-76% and 78-82%, the latter being the higher on the market. The amount of carbon will not exceed 7.5%, silicon will not exceed 1.5%, and sulfur and phosphorus will not exceed 0.03% and 0.3%, respectively. Low phosphorus varieties are also available.
Properties of silicon element
After desulfurization, one of the most important properties of manganese in steel is the stability of martensite even with cold work. In this case, for example, Hadfield steel, which has 15% manganese, can be introduced. Due to the presence of this amount of manganese, the surface of this steel turns into martensite due to cold work and its core will maintain its toughness, so this alloy is very suitable for working in mines and stone crushers.
Ferromanganese is the most common alloy material after carbon and is the most used in ferroalloys. In America, an average of 6.3 kg of ferromanganese is used, and in the world, 7 to 10 kg of this product is used per ton of steel.
Element | Manganese (Mn) | Carbon (C) | Phosphorus (P) | Sulfur (S) | Silicon (Si) |
---|---|---|---|---|---|
Percent | 75-80 | Max 7.5 | Max 0.25 | Max 0.02 | Max 1.5 |