稀土处理无取向硅钢23W1700冶炼全流程夹杂物分析  

Analysis of inclusions in whole smelting process of non-oriented silicon steel 23W1700 by rare earth treatment

作　　者：王涛 陈超[1] 牟望重 薛利强 曹建其 林万明[1,5] WANG Tao;CHEN Chao;MU Wangzhong;XUE Liqiang;CAO Jianqi;LIN Wanming(College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,Shanxi,China;Department of Materials Science and Engineering,KTH Royal Institute of Technology,Stockholm SE-10044,Sweden;No.2 Steelmaking Plant,Shanxi Taigang Stainless Steel Co.,Ltd.,Taiyuan 030030,Shanxi,China;School of Metallurgy and Environment,Central South University,Changsha 410083,Hunan,China;College of New Energy and Materials Engineering,Shanxi Electronic Science and Technology Institute,Linfen 041075,Shanxi,China)

机构地区：[1]太原理工大学材料科学与工程学院,山西太原030024 [2]瑞典皇家工学院材料科学与工程系,瑞典斯德哥尔摩SE10044 [3]山西太钢不锈钢股份有限公司炼钢二厂,山西太原030030 [4]中南大学冶金与环境学院,湖南长沙410083 [5]山西电子科技学院新能源与材料工程学院,山西临汾041075

出　　处：《钢铁》2024年第5期92-103,115,共13页Iron and Steel

基　　金：山西省科技重大专项资助项目(20191102004);山西省回国留学人员科研资助项目(2022-040)。

摘　　要：在无取向硅钢中,微细夹杂物及析出物会严重恶化材料的铁损和磁感应强度。以某企业生产的高牌号无取向硅钢23W1700为研究对象,通过对生产全流程的夹杂物进行研究,采用扫描电子显微镜和能谱仪对夹杂物的形貌、种类和尺寸进行分析并对铸坯中析出相进行计算。结果表明,在无取向硅钢生产过程中,在RH(Ruhrstahl Heraeus)真空精炼处理加铝后,夹杂物主要为Al N,还有少量的Al_(2)O_(3)及其复合夹杂物;RH加稀土后,夹杂物会转变为ReS夹杂物,同时外部包裹少量的AlN夹杂物;加脱硫剂后,主要以小尺寸的Re_(2)O_(2)S为核心且外部包裹AlN的复合夹杂物为主;在中间包浇铸过程中,发现了以ReAlO_(3)或Re_2O_(2)S为核心且外部包裹AlN的复合夹杂物;在铸坯中,发现了球状的MgS,同样发现了与中间包有相同成分的ReAlO_(3)或Re_2O_(2)S为核心的夹杂物,两者只是成分略有差异。在整个冶炼流程中,随着钢液稀土含量的逐步降低,稀土夹杂物的变化趋势主要为ReS→Re_2O_(2)S→ReAlO_(3)。夹杂物平均尺寸主要为2~4μm,其中RH加稀土前夹杂物尺寸最小、RH加稀土后夹杂物尺寸略有增加,RH处理结束后夹杂物尺寸趋于稳定,最终铸坯中夹杂物尺寸为2.9μm左右。利用计算软件Thermo-calc对钢液中夹杂物的析出进行计算,热力学计算结果表明,钢液未凝固时,其夹杂物主要为Al_(2)O_(3),待钢液全部凝固后,会依次析出Ce_(2)O_(2)S、Ce_(2)S_(3)、Al N、Mn S,这也与试验得到的夹杂物类型较为相符。In non-oriented silicon steel,fine inclusions and precipitates can seriously deteriorate the iron loss and magnetic induction strength of material.The inclusions in the whole production process of a high-grade,nonoriented silicon steel 23W1700 which was produced by a steelmaking plant was studied.The morphology,size and type of inclusions were analyzed by scanning electron microscope and energy dispersive spectrometer analysis and the precipitates in the casting process was calculated.The results show that in the production process of non-oriented silicon steel,after adding aluminum in Ruhrstahl Heraeus(RH)Vacuum refining treatment,the primary inclusions are AlN,with a small amount of Al2O3 and its composite inclusions.After adding rare earth alloy to RH,the inclusions will transform into ReS inclusions and some of them are wrapped by AlN inclusion.After adding desulfurizer,the primary inclusions are small-sized Re_(2)O_(2)S wrapped by AlN composite inclusions.In tundish,the inclusions are Re_(2)O_(2)S or ReAlO_(3) as the core and wrapped by AlN composite inclusions.In slab,spherical MgS was found and Re_(2)O_(2)S or ReAlO_(3) cored inclusions with the same composition as in the tundish were also found.And the composition of two types of inclusions is slight different in tundish and slab.Throughout the entire smelting process,as the content of rare earth in liquid steel decreases,the trend of changes in rare earth inclusions is ReS→Re_(2)O_(2)S→ReAlO_(3).The average size of inclusions mainly ranges from 2μm to 4μm,the inclusion size is the smallest before adding rare earth to RH,and the inclusion size increases slightly after adding rare earth to RH.After the completion of RH treatment,the inclusion size tends to stabilize,and ultimately the inclusion average size in the slab is 2.9μm.Using the calculation software Thermo-calc,the precipitation of inclusions in molten steel was calculated.The thermodynamic calculation results showed that when the molten steel was not solidified,the primary inclusions were

关 键 词：无取向硅钢 冶炼全流程 稀土夹杂物 夹杂物分析 析出相计算 

分 类 号：TF76[冶金工程—钢铁冶金]