【摘要】 通过运用氧氮分析仪、金相分析、大样电解分析、扫描电镜及能谱分析等分析手段,研究了LD—氩站—CC生产的低碳钢1个浇次不同浇铸阶段铸坯(头坯、正常坯和尾坯)的洁净度。通过对不同浇铸阶段铸坯的wT[O]和w[N]对比分析可知,开浇时钢水的二次氧化比较严重,浇铸末期钢水的二次氧化较轻;正常坯的显微夹杂物数量为7.96个/mm2,头坯和尾坯的显微夹杂物数量相对正常坯分别升高了约98%和33%,显微夹杂物主要为:Al2O3、Al2O3-(Mn,Fe)S。正常坯中大型夹杂物数量最少,为1.91mg/(10kg);头坯中大型夹杂物数量最高,为8.24mg/(10kg),尾坯中大型夹杂物数量为2.72mg/(10kg),头、尾坯中大型夹杂物多伴有Na、K,说明开浇和浇铸末期结晶器卷渣严重;尾坯中含有较多的MgO-Al2O3和Al2O3-CaO-SiO2-MgO夹杂物,表明浇铸末期发生了中间包漩涡卷渣。更多还原

【Abstract】 By means of Oxygen and Nitrogen Analyzer,Metallographic Examination,SLIME,SEM,EDS,etc.,the cleanliness of low carbon steel slabs(first slab,normal slab and final slab) produced in different casting stages by LD-argon-blowing station-CC.Through the comparative analysis of T[O] and [N] of different casting stages’ slabs,the reoxidation of liquid steel was very serious in casting starting.However,it was not in casting ending.In comparison with the micro-inclusions’ quantity of normal slab(7.96 per square millimeter),the first slab and the final slab respectively increased by 98% and 33%.The component of micro-inclusions were mainly Al2O3 and Al2O3-(Mn,Fe)S.The quantity of large-inclusions was minimal,which was 1.91 mg/(10 kg) in normal slab.While the first slab contained the maximal quantity,it was 8.24 mg/(10 kg).The quantity of large-inclusions was 2.72 kg/(10 kg) in the end slab.Most of large-inclusions contained K or Na elements in the first slab and final slab,which might relate to serious slag entrapment in the mould when the casting starting and ending.The quantity of MgO-Al2O3 inclusions and Al2O3-CaO-SiO2-MgO inclusions was very high in the end slab,which suggested the entrapment in the tundish happened in the casting ending.更多还原