CCSD36钢显微夹杂物

针对唐山某钢铁公司生产的CCSD36钢的生产工艺,采用示踪剂示踪、系统取样、综合分析的方法,对50炉CCSD36钢中氧氮含量进行分析研究,同时对LF处理前后、中间包及铸坯中的显微夹杂的变化进行了系统的分析。研究表明：钢中T[O]、[N]偏高,应加强控制。钙处理前LF炉钢水中的显微氧化物夹杂主要为块状Al2O3夹杂、硅酸盐夹杂,钙处理之后球形钙铝酸盐的数量增加,Al2O3夹杂减少。钙处理效果显著。中间包和铸坯中的夹杂物主要是球形钙铝酸盐及钙铝酸盐与CaS组成的复合夹杂。LF处理前后钢中的显微夹杂数量为102.15个/mm2和55.16个/mm2,去除率达46%,中间包内显微夹杂平均值为39个/mm2,比LF出站时降低29.3%,正常坯显微夹杂物数量的平均值为36个/mm2,与中间包显微夹杂含量相比,只降低7.8%。结合其能谱分析表明,大包到中包及中间包到结晶器二次氧化严重,应加强保护浇注。

Research onMicro Inclusion of CCSD36 Steel

The CCSD36 steel of Tangshan steel company are experimental material in this paper,using tracer, sam- piing system, the method of comprehensive analysis , statistical of oxygen and nitrogen content of CCSD36 in 50 fur-naee respectively,and the data of oxygen and nitrogen content in steel are analyzed. At the same time, changes of micro inclusion in before and after LF processing,tundish and casting were analyzed. The study shows that ：T[ O] [ N] is high in the steel, should strengthen control, especially protection pouring should be strengthened. Micro in-clusions in the steel appear to be silicate inclusions and block and cluster of A1203 before LF treament, after Ca - treatment the number of CaO - A1203 is increased, and the number of A1203 is reduced. Ca - treatment effect is re- markble. CaO-A1203 and CaO-Al2O3 - CaS become the main inclusions in the steel of casting and in tundish. The number of micro inclusion amount to 102. 15/mm^2 and 55.16/mm^2 before and after LF processing, the removal rate of 46% ,and the average number of micro inclusion amount to 39/mm^2 in tundish,29.3% lower than LF,the average number of micro inclusion amount to 36/mm^2 in normal casting, only 7.8 % lower than the number of micro inclusion in the tundish. Combined with its energy spectrum analysis shows that the secondary oxidation phenomenon is serious during the ladle to tundish and tundish to mould, should strengthen the protection pouting.