Manganese is one of the important alloying elements in steel materials. Manganese can change the strength, hardness, toughness, wear resistance, and heat resistance of steel materials and other properties. Manganese in iron and steel materials is mainly obtained by adding ferromanganese alloy to its melt. Ferromanganese can be divided into high carbon, medium carbon, and low carbon ferromanganese due to different carbon content. Among them, high-carbon ferromanganese is strictly restricted due to its high carbon content, and adding it to steel materials will significantly increase the carbon content of the steel. Low-carbon ferromanganese does not have the same problems as high-carbon ferromanganese due to its low carbon content. , an important raw material for wear-resistant steel and structural steel. In the past, the production of low-carbon ferromanganese was mainly through decarburization by blowing oxygen into the liquid high-carbon ferromanganese melt to convert high-carbon ferromanganese into low-carbon ferromanganese, and then reducing the peroxidized melt with silicon-manganese alloy to Improve the yield of manganese. The production process of the high-carbon ferromanganese liquid oxidative decarburization method is complex, high cost, and serious environmental pollution.
Low-carbon ferromanganese is mainly an alloy composed of manganese and iron. It uses manganese ore as raw material and is smelted in blast furnaces and electric furnaces. Ferromanganese is a deoxidizer and is widely used in steelmaking production. alloyed material. The carbon content of low-carbon ferromanganese is not more than 0.7%. The Japanese standard requires a carbon content of less than 1%, while the original Federal German standard requires a carbon content of 0.05~0.5%. The production method of low-carbon ferromanganese is the same as that of medium-carbon ferromanganese, except that the carbon content of the silicon-manganese alloy is required to be lower. In recent years, medium and low-carbon ferromanganese has been produced by the converter, shaker bag, and oxygen-blowing method, which saves energy and reduces carbon content.
Smelting of low-carbon ferromanganese by electrosilicothermal method:
The electrosilicothermal method of smelting low-carbon ferromanganese is to add manganese ore, silicomanganese alloy, and lime into the electric furnace, mainly relying on electric heat to melt the charge, and refine and siliconized the silicomanganese alloy to obtain low-carbon ferromanganese, also known as “de-siliconization”. Silicon method to produce low carbon ferromanganese”. Due to the different states of the charge, it can be divided into the hot charging method and the cold charging method. Its raw materials are manganese ore, silicomanganese alloy, and lime. Manganese in the furnace manganese ore is required to be ≥ 45.0%, Mn/Fe ≥ 7.0, P/Mn ≤ 0.0015%. It is required that Mn≥66%, Si≥17%, C≤1.3%, P≤0.23% in the silicon-manganese alloy require CaO≥85%, P≤0.02%, SiO2≤2.5% in the furnace lime, and use GB3795-87 for smelting Low carbon ferromanganese. The standard requirements for the composition are: Mn≥75.0%, C≤2.0%, Si≤2.5%, P≤0.40%, S≤0.03%. The manufacturer actually controls the composition of low-carbon ferromanganese as follows: about 80% Mn, about 1% Si, about 0.18% P, and S <0.03%. Slag basicity CaO/SiO2 control 1~1.2. The slag contains a lot of manganese, and it generally needs to be diluted or used as a raw material for the production of silicon-manganese alloys to adjust the alkalinity of the slag. The slag composition is about 29% SiO2, about 31% CaO, about 3% MgO, about FeO<1%, about 33% Al2O, and about 30% MnO. The production of 1 ton of medium and low carbon ferromanganese consumes about 1100 kg of manganese ore, 1200 kg of manganese-silicon alloy, and 600 kg of lime. Produce rich slag 1300kg. The unit power consumption is 500 kWh/t. The lining of the electric furnace is made of magnesia bricks. The judgment of the smelting endpoint is based on the external characteristics of the alloy sample. When the alloy silicon is properly controlled, the liquid sample is more viscous, has poor fluidity, more surface wrinkles, darker fractures, fine grains, and is easy to break. When the alloy silicon is high, the surface of the sample is smooth, and the black skin on the surface is completely peeled off after condensation, the fracture is shiny, the crystal grains are coarse, and it is not easy to break. Need to add manganese ore and lime treatment alloy. When the alloy silicon is low, the surface wrinkles are more. High-carbon ferromanganese has dark fractures, and fine grains, and is easy to break. The furnace needs to add manganese silicon alloy.
Ferro Manganese of Anyang Lishi Industrial
Anyang Lishi Industrial has more than 20 years of exporting experience and a professional team. We will assay the product three times— after smelting, after crushing, and before delivery, to promise the quality of our ferroalloy. And we have our own laboratory, sampling inspection of raw materials in the production process, to ensure that each step meets the customer’s standards. Our products have passed ISO 9001 quality management system certification, SGS, BV, CCIC, and CTC certifications. Accept the third part test. If you are looking for Ferro manganese alloys, Please Contact Us Freely!