37Mn5钢精炼过程大尺寸Al_(2)O_(3)-SiO_(2)-MnO类夹杂物形成与演变机理  

Formation and evolution mechanism of large-size Al_(2)O_(3)-SiO 2-MnO inclusions in 37Mn5 steel refining process

作　　者：苗志奇 成国光 李世健 任振海 徐必靖 MIAO Zhiqi;CHENG Guoguang;LI Shijian;REN Zhenhai;XU Bijing(State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing,Beijing 100083,China;Electric Furnace Factory of Zenith Iron Steel Group Co.,Ltd.,Changzhou 213011,China)

机构地区：[1]北京科技大学钢铁冶金新技术国家重点实验室,北京100083 [2]中天钢铁集团电炉厂,江苏常州213011

出　　处：《炼钢》2023年第6期53-58,共6页Steelmaking

摘　　要：为探究37Mn5钢精炼过程尺寸在10μm以上的大尺寸Al_(2)O_(3)-SiO_(2)-MnO类夹杂物的形成与演变机理,在实际“EAF→LF→VD→钙处理→CC”工艺生产37Mn5钢的精炼全流程进行系统取样,检测了钢液成分并重点分析了不同冶炼阶段大尺寸Al_(2)O_(3)-SiO_(2)-MnO类夹杂物的形貌和成分特征,结合实际生产工艺与热力学计算,揭示了这类夹杂物的演变规律。研究结果表明:由于出钢过程局部钢液Al含量低而O含量高,大尺寸Al_(2)O_(3)-SiO_(2)-MnO夹杂物形成;LF精炼初期,局部Ca含量增加形成Al_(2)O_(3)-SiO_(2)-MnO-CaO夹杂物;LF精炼中期以后Ti含量增加会变性前期形成的这两类夹杂物,形成含TiO x的夹杂物,随着冶炼的进行,Ti元素在夹杂物中分布逐渐均匀;VD后钙处理量不足导致夹杂物变性效果不理想,对大尺寸夹杂物的影响不大。出钢过程合理的脱氧、合金化和造渣制度可以减少Al_(2)O_(3)-SiO_(2)-MnO类夹杂物的形成,从而减少夹杂物数量,改善钢材质量。In order to explore the formation and evolution mechanism of large-size Al_(2)O_(3)-SiO_(2)-MnO inclusions with the size of more than 10μm in 37Mn5 steel refining process,the molten steel was systematically sampled during the whole refining process of EAF-LF-VD-calcium treatment-continuous casting for production of 37Mn5 steel.The composition of molte steel was detected,and the morphology and composition characteristics of large-size Al_(2)O_(3)-SiO_(2)-MnO inclusions in different smelting stages were analyzed.Based on actual production process and thermodynamic calculation,the evolution law of this kind of inclusion was revealed.The results show that,due to the low Al content and high O content in local molten steel during EAF tapping process,large-size Al_(2)O_(3)-SiO_(2)-MnO inclusions are formed.At the beginning of LF refining,the local Ca content increases to form Al_(2)O_(3)-SiO_(2)-MnO-CaO inclusions.After the middle stage of LF refining,the Ti content increases to modify the two kinds of inclusions formed at the early stage to form inclusions containing TiO x.With the progress of smelting,the distribution of Ti is gradually uniform in the inclusions.Insufficient calcium treatment after VD results in unsatisfactory modification of inclusions,and has little effect on the large-size inclusions.Reasonable deoxidation,alloying and slagging process can reduce the formation of Al_(2)O_(3)-SiO_(2)-MnO-CaO inclusions,so as to reduce the number of inclusions and improve the quality of steel.

关 键 词：37Mn5钢 钢液精炼 夹杂物 洁净度 

分 类 号：TF769[冶金工程—钢铁冶金]