Ce-La合金化处理对取向硅钢夹杂物特征的影响  

Effect of Ce-La alloying treatment on characteristics of inclusions in grain-oriented silicon steels

作　　者：解晓辉 刘玉龙 李光强[1,2] 陈新元[3] 朱诚意[1,2] XIE Xiao-hui;LIU Yu-long;LI Guang-qiang;CHEN Xin-yuan;ZHU Cheng-yi(The State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China;Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China;School of Mechanical and Automation,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China)

机构地区：[1]武汉科技大学省部共建耐火材料与冶金国家重点实验室,湖北武汉430081 [2]武汉科技大学钢铁冶金及资源利用省部共建教育部重点实验室,湖北武汉430081 [3]武汉科技大学机械自动化学院,湖北武汉430081

出　　处：《钢铁》2021年第11期122-134,共13页Iron and Steel

基　　金：国家自然科学基金面上资助项目(51674180)。

摘　　要：为了研究稀土处理对取向硅钢中夹杂物特征的影响,借助FE-SEM/EDS和图像分析软件分析了稀土处理前后热轧取向硅钢夹杂物的成分、形貌、尺寸和数量并解明了影响机理。研究结果表明,未添加稀土的试验钢中,典型的夹杂物为形貌不规则的MnS-AlN复合夹杂物以及片状或条状的AlN夹杂物;添加稀土后,夹杂物则以球状或椭球状的CeS-LaS、CeS-LaS-AlN、Ce_(2)O_(2)S-La_(2)O_(2)S复合夹杂物和AlN夹杂物为主。稀土处理有效改善了夹杂物形貌,特别是大尺寸氮硫化物的形貌特征,未检测到MnS类夹杂物。尽管加入较多的稀土后夹杂物数量增加,大于5μm夹杂物的平均尺寸增大量明显(增大0.89μm),但整体夹杂物的平均尺寸仅增大了0.40μm。由于稀土的脱硫作用,且稀土硫化物与AlN晶格常数差异大,钢中氮硫化物的数量密度和面积分数降低。稀土降低了AlN在钢中的平衡溶度积,使AlN夹杂物提前析出,导致AlN夹杂物数量增多,且先析出的AlN出现一定程度的长大。稀土对MnS在凝固前沿的析出有抑制作用,有利于热轧和常化过程析出更多用作抑制剂的MnS和AlN。在充分脱氧的取向硅钢中适当降低钢中酸溶铝含量,调整稀土在钢中的用量,在不增加钢中大尺寸夹杂物含量的前提下,发挥MnS、AlN抑制剂作用和Ce-La合金化作用。此外,通过稀土处理控制钢中夹杂物形貌特征,将有望达到改善钢的热轧组织和轧制加工性能的目的。In order to study the effect of rare earth treatment on the characteristics of inclusions in the grain-oriented silicon steels,the composition,morphology,size and quantity of inclusions were analyzed in the hot-rolled grain-oriented silicon steels after rare earth treatment using FE-SEM/EDS and image analysis software,and the effect mechanism was elucidated.The research results show that the typical inclusions were irregular MnS-AlN composite inclusions and flake or strip AlN inclusions in the rare-earth free samples.The inclusions mainly include spherical or ellipsoidal CeS-LaS,CeS-LaS-AlN,Ce_(2)O_(2)S-La_(2)O_(2)S composite inclusions and AlN inclusions in the rare-earth added samples.Rare earth treatment effectively improves the morphology of inclusions,especially the morphology of large size nitrogen sulfide,and no MnS type inclusions were detected in the steel.Although the number of inclusions increases,and the average size of inclusions larger than 5μm increased most obviously(0.89μm)after so much rare-earth added in the steel,the average size of all detected inclusions only increases by 0.40μm.Due to the excellent desulphurization effect of rare-earth and difference of lattice constant between rare-earth sulfide and AlN,the quantity density and area percent of nitrogen sulfide in steel was reduced.The addition of rare earth reduced the equilibrium product of AlN at the solidification front of the steel,leading to more AlN inclusions precipitating,and AlN appears to grow to a certain extent.Rare earth elements inhibit the precipitation of MnS at the solidification front,which is beneficial to the precipitation of more MnS and AlN used as inhibitors during hot rolling and normalizing process.In the fully deoxidized grain-oriented silicon steels,it is expected to exert the inhibition effect of MnS and AlN and alloying effect of Ce-La by appropriately reducing the content of acid-soluble aluminum in the steel and adjusting the addition amount of rare earth in the steel,and large size inclusions don′t gene

关 键 词：取向硅钢 Ce-La合金化 夹杂物 ALN 偏析模型 

分 类 号：TG142.1[一般工业技术—材料科学与工程]