Abstract: The oxygen,nitrogen and inclusion content in liquid steel at converter blowing end point,after added de- oxidizer and alloying at tapping of converter, ladle argon stirred,tundish,and in billet of steel Q235A(0. 14%～0.22% C,0.30%~0.65%Mn)melting by 80 t top and bottom combined blown converter-ladle argon stirring - concasting flow sheet have been examined and analyzed. Results showed that end point oxygen content in steel was 350×10^-6,after added deoxidizer and alloying the oxygen content decreased by 42%,with ladle argon stiring the oxygen content was further de- creased and finally the average oxygen content in billet was ≤25×10^-6;the nitrogen content in steel increased from 20× 10^-6 at converter end point to 40×10^-6 in billet; the inclusion content decreased by about 50% by adding deoxidizer, al- loying and argon stiring,and the inclusion content in billet was ≤45×10^-6;the size of most inclusions was ≤10 μm, and maximum inclusion was 20 μm.

摘要： 检测和分析了80 t顶底复吹转炉.钢包吹氩-连铸流程冶炼Q235A钢(0.14%～0.22%C、0.30%～0.65%Mn)在转炉终点、转炉出钢过程合金化后、钢包吹氩、中间包、钢水和铸坯中的氧、氮和夹杂物含量。结果表明,转炉终点氧含量为350×10^-6,加脱氧剂和合金化后,氧含量降低42%,经钢包吹氩,钢中氧含量进一步降低,铸坯中平均氧含量25×10^-6;钢中氮含量由转炉终点20×10^-6增至铸坯40×10^-6;钢包加脱氧剂、合金化后吹氩,钢中可去除约50%夹杂物,使铸坯中夹杂物含量≤45×10^-6,一般夹杂尺寸≤10μm,最大尺寸为20μm。

关键词: 转炉, Q235A钢, 钢包吹氩, 气体, 夹杂