稀土处理无取向电工钢中非金属夹杂物的演变  

Evolution of non-metallic inclusions in rare-earth treated non-oriented electrical steel

作　　者：胡妍 任强 张立峰 胡志远 程林 HU Yan;REN Qiang;ZHANG Lifeng;HU Zhiyuan;CHENG Lin(School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China;School of Mechanical Engineering,Yanshan University.Qinhuangdao 06600 China;School of Mechanical and Materials Engineering,North China University of Technology,Beijing 100144,China;Shougang Zhixin Qian'an Electromagnetic Material Co.,Ltd.,Qian?an 064400,China)

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083 [2]燕山大学机械工程学院,河北秦皇岛066004 [3]北方工业大学机械与材料工程学院,北京100144 [4]首钢智新迁安电磁材料有限公司,河北迁安064400

出　　处：《炼钢》2022年第3期48-57,68,共11页Steelmaking

基　　金：河北省自然科学基金资助项目(E2021203062);河北省省级科技计划资助项目(20311005D)。

摘　　要：使用自动扫描电镜分析了镧铈混合稀土处理无取向电工钢生产全流程钢中夹杂物的形貌、数量和尺寸,采用ICP-MS测量了各个阶段钢中的总镧(TLa)和总铈(TCe)的含量。通过分析可知,在加入稀土前,钢中的氧化物夹杂主要为镁铝尖晶石;加入稀土后,钢中的夹杂物被改性为(RE)_(2)O_(2)S、(RE)AlO_(3)以及它们的复合夹杂物,此外还有少量的(RE)S。随着钢中TLa质量分数从1×10^(-6)增加到10×10^(-6),TCe质量分数从5×10^(-6)增加到18×10^(-6),夹杂物的改性规律为:Al_(2)O_(3)·MgO→(RE)AlO_(3)→(RE)_(2)O_(2)S、(RE)AlO_(3)双相夹杂物→(RE)_(2)O_(2)S→(RE)S。随着冶炼过程中钢中稀土含量的减少,(RE)_(2)O_(2)S、双相夹杂物((RE)_(2)O_(2)S+(RE)AlO_(3))数量递减,而尺寸基本维持在2μm左右;(RE)AlO_(3)数量先增加后减少,在中间包钢液中达到最大值,此时尺寸在2~5μm,在连铸坯中尺寸又减小到2μm左右;中间包钢液中(RE)S数量较少,尺寸在1μm左右,连铸坯中(RE)S的尺寸增加,在2~3μm。通过热力学计算得到在1473 K条件下,钢中生成的稀土夹杂物有(RE)_(2)O_(2)S、(RE)AlO_(3)以及它们的复合夹杂物以及(RE)S。The morphology,quantity and size of inclusions in non-oriented electrical steel treated with lanthanum and cerium were analyzed by automatic scanning electron microscope(SEM),and the contents of total lanthanum(TLa)and total cerium(TCe)in steel were measured by ICP-MS.The analysis showed that before the addition of rare earth,the oxide inclusions in the steel were mainly magnesia spinel.With the addition of rare-earth elements,the inclusions in the steel were modified into(RE)_(2)O_(2)S,(RE)AlO_(3) and their composite inclusions,in addition to a small amount of(RE)S.The modification law of the inclusion was as follows:Al_(2)O_(3)·MgO→(RE)AlO_(3)→(RE)_(2)O_(2)S,(RE)AlO_(3) bi-phase inclusions→(RE)_(2)O_(2)S→(RE)S,as the TLa mass fraction in steel increased from 1×10^(-6) to 10×10^(-6) and the TCe mass fraction in steel increased from 5×10^(-6)to 18×10^(-6).The number of(RE)_(2)O_(2)S and dual-phase inclusions(RE)_(2)O_(2)S+(RE)AlO_(3) decreased with the decrease of rare earth content in the steel during smelting,and the size of them was maintained at about 2μm.The quantity of(RE)AlO_(3) increased first and then decreased,and reached the maximum value in molten tundish steel with the size of about 2-5μm,and then decreased to about 2μm in continuous casting slab.The size of(RE)S in molten tundish steel was about 1μm,and the size of(RE)S in continuous casting slab was about 2-3μm.Thermodynamic calculation showed that the rare earth inclusions were(RE)_(2)O_(2)S,(RE)AlO_(3),their composite inclusions and(RE)S in steel at 1473 K.

关 键 词：稀土 夹杂物 改性机理 尺寸 无取向电工钢 

分 类 号：TF764[冶金工程—钢铁冶金]