Ferro-Silicon

Ferro-Silicon Ferro-silicon (Fe-Si) is a metallic ferro-alloy having iron (Fe) and silicon (Si) as its main elements. In commercial terminology It is defined as a ferro-alloy containing 4 % or more of Fe, more than 8 % but not more than 96 % of Si, 3 % or less phosphorus (P), 30 % or less of manganese (Mn), less than 3 % of magnesium (Mg), and 10 % or less any other element. However, the regular grades of the ferro-alloy normally contain Si in the range of 15 % to 90 %. The usual Si contents in the Fe-Si available in the market are 15 %, 45 %, 65 %, 75 %, and 90 %. The remainder is Fe and minor elements. The minor elements, such as aluminum (Al), calcium (Ca), carbon (C), manganese (Mn), phosphorus (P), and sulphur (S) are present in small percentages in Fe-Si. Commercially, Fe-Si is differentiated by its grade and size. Fe-Si grades are defined by the percentages of Si and minor elements contained in the product. The principal characteristic is the percentage of Si contained in the ferro-alloy and the grades are referred to primarily by reference to that percentage. Hence 75 % Fe-Si contains around 75 % of Si in it. Fe-Si grades are further defined by the percentages of minor elements present in the product. ‘Regular grade 75 % Fe-Si’ denote that the product containing the indicated percentages of Si and recognized maximum percentages of minor elements. Other grades of Fe-Si differ from regular grades by having more restrictive limits on the content of elements such as Al, titanium (Ti), and/or Ca in the ferro-alloy. Fe-Si is also produced in a grade that contains controlled amounts of minor elements for the purpose of adding them to...

Production of Ferro-Silicon Jun27

Production of Ferro-Silicon...

Production of Ferro-Silicon Ferro-silicon (Fe-Si) is a ferro-alloy having iron (Fe) and silicon (Si) as its main elements. The ferro-alloy normally contains Si in the range of 15 % to 90 %. The usual Si contents in the Fe-Si available in the market are 15 %, 45 %, 65 %, 75 %, and 90 %. The remainder is Fe, with around 2 % of other elements like aluminum (Al) and calcium (Ca). Fe-Si is produced industrially by carbo-thermic reduction of silicon dioxide (SiO2) with carbon (C) in the presence of iron ore, scrap iron, mill scale, or other source of iron. The smelting of Fe-Si is a continuous process carried out in the electric submerged arc furnace (SAF) with the self-baking electrodes. Fe-Si (typical qualities 65%, 75% and 90% silicon) is mainly used during steelmaking and in foundries for the production of C steels, stainless steels as a deoxidizing agent and for the alloying of steel and cast iron. It is also used for the production of silicon steel also called electrical steel. During the production of cast iron, Fe-Si is also used for inoculation of the iron to accelerate graphitization. In arc welding Fe-Si can be found in some electrode coatings. The ideal reduction reaction during the production of Fe-Si silicon is SiO2+2C=Si+2CO. However the real reaction is quite complex due to the different temperature zones inside the SAF. The gas in the hottest zone has a high content of silicon mono oxide (SiO) which is required to be recovered in the outer charge layers if the recovery of Si is to be high. The recovery reactions occur in the outer charge layers where they heat the charge to a very high temperature. The outlet gas form the furnace contains SiO2 which can...

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...

Silico- Manganese

Silico- Manganese Silico-manganese (Si-Mn) is a metallic ferro alloy which is being used to add both silicon (Si) and manganese (Mn) as ladle addition during steelmaking. Because of its lower carbon (C) content, it is a preferred ladle addition material during making of low carbon steels. Si-Mn is a ferroalloy composed principally of Mn, Si, and Fe (iron), and normally contains much smaller proportions of minor elements, such as C, phosphorus (P), and sulphur (S). The ferroalloy is also sometimes referred to as ferro-silicon-manganese. Both Mn and Si play an important role in the manufacturing of steel as deoxidizing, desulphurizing, and alloying agents. Si is the primary and more powerful deoxidizer. Mn is a milder deoxidizer than Si but enhances the effectiveness of the latter due to the formation of stable manganese silicates and aluminates. It also serves as desulphurizer. 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. There are two families of Mn alloys one is called Si-Mn while the other is known as ferro-manganese (Fe-Mn). Si-Mn adds additional silicon in liquid steel which is a stronger deoxidizer and which also helps to improve some mechanical properties of steel. In each family, content of C can be controlled and lowered when producing low C grades. 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. The Fe-Mn grades are high carbon (HC), medium carbon (MC), low-carbon (LC) and very low carbon (VLC), whereas the Si-Mn grades include medium carbon (MC) and low carbon (LC). The steel industry is the only consumer of these alloys. However...