Ferro-Manganese

Ferro-Manganese Ferro-manganese (Fe-Mn) is a metallic ferro alloy which is added usually along with ferro-silicon (Fe-Si) as ladle addition during steelmaking. It is a ferroalloy composed principally of manganese (Mn) and iron (Fe), and normally contains much smaller proportions of minor elements, such as carbon (C), phosphorus (P), and sulphur (S). Fe-Mn is an important additive used as a deoxidizer in the production of steel. It is a master alloy of Fe and Mn with a minimum Mn content of 65 %, and maximum Mn content of 95 %. There are two families of Mn alloys. One is called Fe-Mn while the other is known as silico-manganese (Si-Mn). Around 93 % of all the Mn produced is in the form of Mn ferroalloys consists of the Fe-Mn grades and the Si-Mn grades. Mn plays an important role in the manufacturing of steel as deoxidizing, desulphurizing, and alloying agent. It is a mild deoxidizer than silicon (Si) but enhances the effectiveness of the latter due to the formation of stable manganese silicates and aluminates. Mn is used as an alloying element in almost all types of steel. Of particular interest is its modifying effect on the iron-carbon (Fe-C) system by increasing the hardenability of the steel. Fe-Mn is produced in a number of grades and sizes and is consumed in bulk form primarily in the production of steel as a source of Mn, although some Fe-Mn is also used as an alloying agent in the production of iron castings. Mn, which is intentionally present in nearly all steels, is used as a steel desulphurizer and deoxidizer. Mn improves the tensile strength, workability, toughness, hardness and resistance to abrasion. By removing S from steel, Mn prevents the steel from becoming brittle during the hot rolling process....

Production of Ferro- Manganese Jun19

Production of Ferro- Manganese...

Production of Ferro- Manganese Ferro-manganese (Fe-Mn) is an important additive used as a deoxidizer in the production of steel. It is a master alloy of iron (Fe) and manganese (Mn) with a minimum Mn content of 65 %, and maximum Mn content of 95 %. It is produced by heating a mixture of the oxides of Mn (MnO2) and iron (Fe2O3) with carbon (C) normally as coke or coal. Fe-Mn in a blast furnace (BF) with considerably higher Mn content than was possible earlier was first produced in 1872 by Lambert Von Pantz. The Fe-Mn produced had 37 % Mn instead of 12 % being obtained earlier. Metallurgical grade Mn ores having Mn content higher than 40 % are usually processed into suitable metallic ferro- alloy forms by pyro-metallurgical processes, which are very similar to the iron pyro-metallurgical processes. In its production process, a mixture of Mn ore, reductant (a form of C) and flux (CaO) are smelted at a temperature which is higher than 1200 deg C to enable reduction reactions and alloy formation. Standard grades of Fe-Mn can be produced either in a BF or in an electric submerged arc furnace (SAF). The electric SAF process, however, is far more flexible than the BF process, in that slags can be further processed to Si-Mn and refined Fe-Mn. The choice of process is also dependent on the relative price of electric power and coke. In a three-phase SAF, the electrodes are buried in the charge material. The raw materials are heated and the Mn oxides pre-reduced by hot carbon mono oxide (CO) gas form the reaction zones deeper in the furnace. The exothermic reactions contribute favourably to the heat required. Efficient production of HC Fe-Mn depends on the degree of pre-reduction which occurs...