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以金红石、钛精矿、Al为原料采用铝热自蔓延法制备出低氧高钛铁。研究相关反应体系的热力学及动力学问题,考察配料比、熔渣类型、发热剂等对铝热自蔓延过程的影响,采用XRD,SEM以及化学分析等技术对高钛铁合金进行表征。结果表明:反应体系的绝热温度大于1800K,反应能自我维持进行;Al还原TiO2反应的表观活化能为93.676kJ.mol-1,反应级数为0.01,Al还原TiO2和Fe2O3的表观活化能为300.740kJ.mol-1,反应级数为1.20;合金主要由TiFe2、TiFe以及Fe2TiO0.13等钛铁低氧固溶体相组成,夹杂相存在是导致合金中氧含量高及微观缺陷存在的直接原因;合金中钛、铝、铁、硅含量分别为:60.0%～62%、7.0%～11.0%、21.0%～25.0%以及3.0%左右;合金中的氧被有效去除,最低为1.85%。
Using rutile, titanium concentrate and Al as raw materials, low-oxygen and high-Ti ferrite was prepared by aluminothermic self-propagation method. The thermodynamics and kinetics of the reaction system were investigated. The influence of the ratio of ingredients, slag type and heating agent on the thermal self-propagation of aluminum was investigated. The high-titanium ferroalloy was characterized by XRD, SEM and chemical analysis. The results show that the adiabatic temperature of reaction system is more than 1800K, and the reaction can maintain itself. The apparent activation energy of Al-reduced TiO2 reaction is 93.676kJ · mol-1, the reaction order is 0.01, the apparent activation energy of Al-reduced TiO2 and Fe2O3 Is 300.740kJ · mol-1, the reaction order is 1.20. The alloy is mainly composed of TiFe2, TiFe and Fe2TiO0.13 and other ilmenite low-oxygen solid solution phase. The inclusion phase is the direct cause of high oxygen content and microscopic defects in the alloy The contents of titanium, aluminum, iron and silicon in the alloy are respectively 60.0% -62%, 7.0% -11.0%, 21.0% -25.0% and 3.0%. The oxygen in the alloy is effectively removed and the minimum is 1.85%.