第36卷第7期 北京科技大学学报 Vol.36 No.7 2014年7月 Journal of University of Science and Technology Beijing Jul.2014 交换钢包过程对F钢连铸板坯表层洁净度的影响 邓小旋2四，王新华”，李林平”，魏鹏远”，季晨曦》，曾智》，田志红) 1)北京科技大学治金与生态工程学院，北京1000832)首钢技术研究院，北京1000433)首钢京唐公司炼钢部，唐山063200 ☒通信作者，E-mail:d042@163.com 摘要采用ASPEX扫描电镜中的自动特征分析功能研究了交换钢包过程（取样浇次第4、5炉）对F钢连铸板坯表层的洁 净度的影响，且对比研究了交换钢包过程浇铸铸坯（交接坯）与正常浇铸铸坯（正常坯）的表层洁净度.结果表明：正常坯与交 接坯中尺寸大于20um的表层夹杂物可分为三类：(1)簇群状A山，03（包括气泡+簇群状A山，0，）：(2)簇群状T0,-AL,0,夹杂 物：(3)保护渣夹杂物.正常坯表层的大型夹杂物主要为簇群状A山0，没有检测到保护渣夹杂物.换包开浇后铸坯总氧质量 分数从14×106增至17×106，交接坯表层检测到较多的第2夹杂物，说明钢包开浇后钢水被轻微氧化.此外，钢包开浇后剧 烈的液面波动也导致了保护渣的卷入.在当前工艺下，换包对F钢铸坯表层洁净度的影响长度约为11m 关键词F钢：连铸；铸坯：表面：洁净度：夹杂物：氧化铝 分类号TF777.1 Effect of ladle change process on the surface cleanliness of IF steel continuous casting slabs DENG Xiao--an.2,WANG Xin-:hua”,Lin-ping》,WEl Peng-yuan”,JIChen--,ZENG Zh2,TIAN Zhi-hong》 1)School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China 2)Shougang Research Institute of Technology Beijing 100043,China 3)Steelmaking Department,Shougang Jingtang United Iron Steel Co.,Lid.,Tangshan 063200,China Corresponding author,E-mail:dxx042@163.com ABSTRACT The effect of ladle change process (the 4th heat to the 5th heat)on the surface cleanliness of IF steel continuous cast- ing slabs was investigated by total oxygen measurement and automatic feature analysis equipped on ASPEX.A comparison of surface cleanliness was performed between transition slabs (cast during ladle change process)and normal slabs (cast under normal condi- tion).It is found that inclusions larger than 20pm are classified into three types:(1)cluster alumina (including bubble cluster a- lumina inclusions);(2)cluster TiO,Al2O,inclusions:and (3)mold powder inclusions.In terms of surface inclusions in normal slabs,most of the inclusions detected in the scanning area are cluster alumina,and no mold powder inclusions are found.While for transition slabs,the total oxygen content increases from 14x10to 17x10,and the number density of Type 2 inclusions goes up since the cast start of the 5th heat,indicating re-oxidation of the steel melt during ladle change process.Furthermore,level fluctuation in the mold is also severe since the cast start of the 5th heat,leading to mold powder entrapments.The affected length of cast slabs dur- ing ladle change process is about 11 m under the present casting condition. KEY WORDS IF steel;continuous casting:slabs:surfaces:cleanliness;inclusions:alumina 钢中大型非金属夹杂物被认为是引起以汽车板 碾碎、拉长，形成所谓的线条状缺陷，极大地影响了 为代表的冷轧板卷表面缺陷的主要原因，这些分 F钢后续的涂镀性能.因此为了减少成品的缺陷 布在铸坯表层的大型夹杂物在后续的轧制过程中被 率，对铸坯的表层大型非金属夹杂物数量有严格的 收稿日期：2013-0505 基金项目：国家重点基础研究发展计划资助项目(2010CB30806) DOI:10.13374/j.issn1001-053x.2014.07.005:http://journals.ustb.edu.cn第 36 卷 第 7 期 2014 年 7 月 北京科技大学学报 Journal of University of Science and Technology Beijing Vol． 36 No． 7 Jul． 2014 交换钢包过程对 IF 钢连铸板坯表层洁净度的影响 邓小旋1，2) ，王新华1) ，李林平1) ，魏鹏远1) ，季晨曦2) ，曾 智2) ，田志红3) 1) 北京科技大学冶金与生态工程学院，北京 100083 2) 首钢技术研究院，北京 100043 3) 首钢京唐公司炼钢部，唐山 063200  通信作者，E-mail: dxx042@ 163． com 摘 要 采用 ASPEX 扫描电镜中的自动特征分析功能研究了交换钢包过程( 取样浇次第 4、5 炉) 对 IF 钢连铸板坯表层的洁 净度的影响，且对比研究了交换钢包过程浇铸铸坯( 交接坯) 与正常浇铸铸坯( 正常坯) 的表层洁净度． 结果表明: 正常坯与交 接坯中尺寸大于 20 μm 的表层夹杂物可分为三类: ( 1) 簇群状 Al2O3 ( 包括气泡 + 簇群状 Al2O3 ) ; ( 2) 簇群状 TiOx--Al2O3夹杂 物; ( 3) 保护渣夹杂物． 正常坯表层的大型夹杂物主要为簇群状 Al2O3，没有检测到保护渣夹杂物． 换包开浇后铸坯总氧质量 分数从 14 × 10 － 6增至17 × 10 － 6，交接坯表层检测到较多的第 2 夹杂物，说明钢包开浇后钢水被轻微氧化． 此外，钢包开浇后剧 烈的液面波动也导致了保护渣的卷入． 在当前工艺下，换包对 IF 钢铸坯表层洁净度的影响长度约为 11 m． 关键词 IF 钢; 连铸; 铸坯; 表面; 洁净度; 夹杂物; 氧化铝 分类号 TF 777. 1 Effect of ladle change process on the surface cleanliness of IF steel continuous casting slabs DENG Xiao-xuan1，2)  ，WANG Xin-hua1) ，LI Lin-ping1) ，WEI Peng-yuan1) ，JI Chen-xi2) ，ZENG Zhi2) ，TIAN Zhi-hong3) 1) School of Metallurgical and Ecological Engineering，University of Science and Technology Beijing，Beijing 100083，China 2) Shougang Ｒesearch Institute of Technology Beijing 100043，China 3) Steelmaking Department，Shougang Jingtang United Iron ＆ Steel Co． ，Ltd． ，Tangshan 063200，China  Corresponding author，E-mail: dxx042@ 163． com ABSTＲACT The effect of ladle change process ( the 4th heat to the 5th heat) on the surface cleanliness of IF steel continuous cast￾ing slabs was investigated by total oxygen measurement and automatic feature analysis equipped on ASPEX． A comparison of surface cleanliness was performed between transition slabs ( cast during ladle change process) and normal slabs ( cast under normal condi￾tion) ． It is found that inclusions larger than 20 μm are classified into three types: ( 1) cluster alumina ( including bubble + cluster a￾lumina inclusions) ; ( 2) cluster TiOx-Al2 O3 inclusions; and ( 3) mold powder inclusions． In terms of surface inclusions in normal slabs，most of the inclusions detected in the scanning area are cluster alumina，and no mold powder inclusions are found． While for transition slabs，the total oxygen content increases from 14 × 10 － 6 to 17 × 10 － 6，and the number density of Type 2 inclusions goes up since the cast start of the 5th heat，indicating re-oxidation of the steel melt during ladle change process． Furthermore，level fluctuation in the mold is also severe since the cast start of the 5th heat，leading to mold powder entrapments． The affected length of cast slabs dur￾ing ladle change process is about 11 m under the present casting condition． KEY WOＲDS IF steel; continuous casting; slabs; surfaces; cleanliness; inclusions; alumina 收稿日期: 2013--05--05 基金项目: 国家重点基础研究发展计划资助项目( 2010CB30806) DOI: 10． 13374 /j． issn1001--053x． 2014． 07． 005; http: / /journals． ustb． edu． cn 钢中大型非金属夹杂物被认为是引起以汽车板 为代表的冷轧板卷表面缺陷的主要原因［1］，这些分 布在铸坯表层的大型夹杂物在后续的轧制过程中被 碾碎、拉长，形成所谓的线条状缺陷，极大地影响了 IF 钢后续的涂镀性能． 因此为了减少成品的缺陷 率，对铸坯的表层大型非金属夹杂物数量有严格的