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The high ilmenite is a wider use of Special Ferroalloy smelting iron base superalloys and high-quality stainless steel materials indispensable, especially the irreplaceable role in improving the quality of the military, aviation and other high alloy steel. With the improvement of the quality requirements for steel, ilmenite quality requirements are also increasing. The high ilmenite Preparation aluminum thermal reduction method. The wide source of raw materials, cheap, low production costs. High ilmenite obtained because the oxygen content is too high, can not meet the user requirements, the limited use of the high ilmenite. Our high quality ilmenite are imported from abroad, the cost is extremely high, and has seriously hampered the development of China's high-tech. Thermite prepared high ilmenite current process from the start by analyzing the formation mechanism of the high ilmenite microstructure and oxygen, aluminum thermal reduction - vacuum refining prepared hypoxia-quality high ilmenite new technology, that is, first The use of aluminum thermal reduction were prepared the high ilmenite crude product, and then vacuum refining. By adding compound reducing agent composed of a complex with slag, removal of the high ilmenite inclusions prepared hypoxia of high quality titanium ferroalloy. Microstructure analysis shows that, the existing aluminum thermal reduction of the production of the high ilmenite reduction reaction is incomplete, oxygen elements mainly Al 2 the O 3 Fe 2 (MLR) models are checked, of TiO 2 Ti 2 O, titanium oxygen solid solution of oxygen, such as complex microstructure formed chemically stable oxide inclusions, slag - gold separation difficult. Even if the extension of the holding time when the high temperature melting, to improve the high ferrotitanium slag - the separation conditions, but from the oxygen in the air also result the ilmenite in oxygen concentration due to diffusion, and is difficult to obtain hypoxia. Based on the analysis of the composition and oxygen formation mechanism of high titanium ferroalloy inclusions, select the Al-Mg composite reducing agent was investigated slag viscosity of CaO-Al 2 the O 3 -CaF 2 -based slag system the to select the CaO-Al 2 O 3 -CaF 2 -TiO 2 and CaO-Al 2 the the O 3 -CaF 2 -SiO 2 meta-slag system were investigated TiO 2 and the SiO 2 content viscosity and fluidity of slag system, measuring the viscosity of the slag samples, analysis of its phase change. The viscosity tests showed: the slag viscosity decreased as the temperature rises, 2 increase decreases with as CaF . The of of CaO-Al 2 O 3 -CaF 2 -TiO 2 slag system at a temperature above 1520 ℃ The viscosity is less than 0.4 Pa · S, good fluidity of the slag. Smelting slag phase: 3 CaO · Al 2 O , 3 1 2 CaO · 7Al 2 O 3 , Ca1 2 Al14O 3 2 F 2 , 3 (the AlO 3 ) 2 the CaTiO 3 . The of of CaO-Al 2 O 3 -CaF 2 -SiO 2 slag system at a temperature above 1492 ℃ viscosity less than 0.4 Pa.s, good fluidity of the slag; viscosity decreases with increase of SiO 2 amount reduced. Smelting slag phase for Ca1 2 Al14O 3 2 F 2 , Ca 2 SiO 4 , Ca 2 SiO 2 F 2 , Ca 3 Al < sub> 2 (SiO 4 ) 3 , 5CaO · 3 Al 2 O 3 and Al 2 (the SiO 4 ) O. The vacuum refining tests showed: Al-(10% << / sup> sub> 2 0%) Mg is an effective composite reductant, CaO-(10% 2 0%) the CaF 2 - (10% 1 5% of) Li 2 O is a good slag system, the elimination of the high titanium iron oxide inclusions, is very effective to reduce the oxygen content in the alloy. After vacuum refining, an alloy of aluminum, the silicon content had been achieved, the oxygen content was 3.25%, compared with 12.20% and the oxygen content of the crude ilmenite has been effectively reduced.
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