【作者】 罗艳； 张莹； 张立峰； 陈凌峰； 程林； 胡志远；

【Author】 LUO Yan;ZHANG Ying;ZHANG Li-feng;CHEN Ling-feng;CHENG Lin;HU Zhi-yuan;School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing;Qian’an Steelmaking Co.,Ltd.,Shougang Group;

【机构】 北京科技大学冶金与生态工程学院； 首钢迁安钢铁有限责任公司；

【摘要】 对生产超低碳钢中的中间包冶炼工序进行了钢水中的洁净度调研。通过在中间包中多级取样,系统分析钢中的T[O]、[N]含量及钢中非金属夹杂物来评估中间包洁净度。采用多种夹杂物评估方法,对钢中的夹杂物进行分类、尺寸统计、形貌、数量等行为的研究。结果表明:超低碳钢在中间包冶炼过程中T[O]和[N]质量分数分别控制在6×10^-6和20×10^-6左右,表明中间包对长水口的密封效果较好。钢中的夹杂物以带棱角的A1N为主,占总夹杂物的55%,密度分布为26个/mm²,尺寸小于4μm。所有类型的夹杂物尺寸主要在8μm以下,其中以2³μm为主,占41%。通过对全氧、氮含量和夹杂物分析得出超低碳钢在中间包冶炼过程中已是高洁净度技术。采用了Thermo-Calc热力学计算软件计算出该钢样中AlN、MnS析出温度分别为1 320、1 000℃,而Al₂O₃析出温度大于1 600℃,从而为钢中析出相顺序提供了理论依据。更多还原

【Abstract】 Investigation of steel cleanliness of ultra-low carbon steel in continuous casting tundish was performed in the current paper.The total oxygen and nitrogen content and non-metallic inclusions were evaluated by the method of MSSA（multistage sampling and system analysis）.The composition,size,amount,morphology and location of inclusions in steel samples were reported.For the current high clean steel,the total oxygen and nitrogen content in tundish were controlled to 6 × 10^-6 and 20 × 10^-6 respectively.One of the primary inclusions were angular<4 μm nitrides（A1N） that were 55%of the total number of inclusions and their number density was 26 per mm2.Other inclusions such as oxides and sulfides could be as big as 8 μm,while 40%of them were<2 μm.The calculation using Thermo-Calc thermodynamic software shows that the precipitation temperature of A1 N and MnS are 1 320 ℃ and1 000 ℃,respectively,and the precipitation of A1₂O₃ occurs over 1 600 ℃.更多还原