超低氧车轮钢精炼过程非金属夹杂物的转变  

Transformation of non-metal inclusions in ultra-low oxygen wheel steel during refining process

作　　者：杨俊[1] 王新华[1] 王万军[1] 龚志翔[2] 汪国才[2] 唐宇[1] 

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083 [2]马鞍山钢铁股份有限公司技术中心,马鞍山243011

出　　处：《北京科技大学学报》2010年第7期860-865,882,共7页Journal of University of Science and Technology Beijing

基　　金：国家重点基础研究发展计划资助项目(No.2010CB630806)

摘　　要：研究了采用LD-LF-VD-CC工艺流程生产超低氧高速车轮钢时,精炼过程中夹杂物的生成与变化.实验在出钢时加入足够的Al进行终脱氧,LF精炼过程采用强脱氧、高碱度和强还原性精炼渣工艺,能使最终铸坯w(T.O)达到7×10-6,获得高洁净度的铸坯;而且在LF精炼过程中,夹杂物完成了Al2O3→MgO.Al2O3→CaO-MgO-Al2O3类复合夹杂物的转变,得到在炼钢温度下呈液态的复合氧化物夹杂,这些液态夹杂物通过碰撞、长大和上浮去除,残留于钢中的氧化物夹杂以较低熔点的CaO-MgO-Al2O3类复合夹杂形态存在,它们在热加工过程中可以发生稍许变形,能有效改善车轮钢的疲劳性能.The formation and transformation of inclusions in high speed wheel steel during refining were studied in ultra-low oxygen steelmaking by LD-LF-VD-CC process. Sufficient aluminium was added to the experimental steel for final deoxidation during tapping,and refining slag with strong deoxidation,high basicity and strong reducibility was used during LF refining. The results show that the casting blanks are of high cleanliness and the total oxygen is only 7×10-6. Oxide inclusions in the experimental steel have finished the transformation of Al2O3 → MgO·Al2O3 spinel → CaO-MgO-Al2O3 complex inclusions during LF refining,and the complex oxide inclusions obtained are liquid and easy to remove by collision,coalescence and flotation at steelmaking temperature. Residual oxide inclusions in the steel are CaO-MgO-Al2O3 system complex inclusions with a relatively lower melting point,which have a little deformability during hot-working and can improve the fatigue properties of high speed wheel steel effectively.

关 键 词：车轮钢 脱氧 氧化物夹杂 三元相图 

分 类 号：TF769.2[冶金工程—钢铁冶金]