重轨钢全铝控制

Control of Total Content of Aluminium in Heavy Rail Steel

针对重轨钢中铝含量高导致重轨缺陷率高的问题,分析了影响钢中铝含量的因素。采取了转炉低碳出钢和低铝合金冶炼,使用重轨专用罐盛钢,优化LF顶渣碱度为2.0~2.5,采取高过热度(25~30℃)浇注等措施后,重轨钢钢水中的铝含量稳定控制在25×10^(-6),缺陷率由0.30%降低到0.25%以下,满足了重轨钢的生产要求。

In view of the problem that the high content of aluminium in heavy rail steel led to the high rate of defect in terms of the heavy rail, the factors influencing the content of aluminium in the steel were analyzed. After that, taking such countermeasures as tapping molten steel from converter with low content of carbon and carrying out the smelting process in converter with low content of aluminium alloy, applying a special ladle for molten steel for heavy rails, optimizing the top slag alkalinity to be in the range from 2.0 to 2.5 for LF, casting molten steel at high degree of overheat(from 25 ℃ to 30 ℃), the content of aluminium in molten steel for heavy rails could be controlled stably within 25 ×10^(-6), while the ratio of defect was reduced to less than 0.25% from0.30%, which met the requirements asked by producing heavy rail steels.