镀锡基板钢LF精炼过程洁净度研究  

Cleanliness study of tin plate steel during LF process

作　　者：贾雅楠[1,2] 朱立光 张彩军 裴培[3] 

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083 [2]华北理工大学高品质钢连铸实验室,河北唐山063000 [3]首钢京唐钢铁有限公司,河北唐山063000

出　　处：《炼钢》2016年第1期35-41,共7页Steelmaking

基　　金：河北省高等学校科学技术研究项目(Z2014019);河北省科技计划项目(1321101018D)

摘　　要：为了解BOF→LF→CC工艺生产的MRT-2.5镀锡板洁净度变化情况,系统取样分析了LF精炼过程中钢中总氧、氮含量变化,研究了LF精炼过程中夹杂物的类型、数量及尺寸的变化,并分析了不同阶段夹杂物的转变机理。结果表明:LF精炼结束后,钢中w(T.O)=34.8×10^(-6),w(N)=21.1×10^(-6);LF精炼过程夹杂物的主要类型为:成渣后以Mg O-Al2O3为主,加铝后以Al2O3为主,钙处理结束后夹杂物以CaS-MgO-CaO-Al2O3为主;LF精炼过程中夹杂物数量总体呈下降趋势,LF精炼结束后,夹杂物数量达到3.9个/mm^2,夹杂物粒径范围逐渐向0~5μm集中;某公司钢水条件下,若生成CaO-MgO-Al_2O_3系低熔点夹杂物应控制w(Mg)=(0.45~8)×10^(-6),w(Ca)=(2~20)×10^(-6),a(O)=(2~6)×10^(-6),且为避免CaS夹杂的析出,w(S)应控制在0.004 2%以下。In order to understand the cleanliness of MRT-2.5 tin plate steel by a BOF→LF→CC route, the system sampling was performed to analysis the content of nitrogen and total oxygen in liquid steel during LF refining, and variation of the types of inclusions, number and size of inclusions were studied during LF process. Transformation mechanism of inclusions was also studied at different stages. The experimental results show that, w（T. O） = 34.8 × 10^-6 and w（N） = 21.1 × 10^-6 at the end of LF refining. The main types of oxide inclusions are MgO-Al2O3 after slag forming, Al2O3 after aluminum addition, and CaS-CaO-Al2O3 at the end of calcium treatment. The number density of inclusions which decreases during LF refining is 3.9/mm^2 at the end of LF refining and the diameter of inclusion particle size is gradually concentrated in the range of 0 - 5μm. Under the conditions in a company, w（Ca）, w （Mg）, a （0） in liquid steel should be controlled in （2 - 20） × 10^-6, （0.45 - 8） × 10^-6, （2 - 6） × 10^-6 in order to control inclusions in low melting point and w（S） should be controlled less than 0. 004 2 % in order to avoid CaS inclusions with precipitation.

关 键 词：镀锡板 LF精炼 夹杂物 洁净度 

分 类 号：TF769.2[冶金工程—钢铁冶金]