精炼渣Al_(2)O_(3)含量对铝脱氧钢中夹杂物的影响  

Effect of Al_(2)O_(3) content in refining slag on non-metallic inclusions in Al-killed steel

作　　者：于会香[1] 邱光元 郝丽霞 赵艳宇[2] 王新华[1] YU Huixiang;QIU Guangyuan;HAO Lixia;ZHAO Yanyu;WANG Xinhua(School of Metallurgical and Ecological Engineering,University of Science and Technology,Beijing 100083,China;Steelmaking Operation Department,Beijing Shougang Co.,Ltd.,Qian an 064404,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]北京首钢股份有限公司炼钢作业部,河北迁安064404

出　　处：《炼钢》2023年第2期18-23,共6页Steelmaking

基　　金：国家重点研发计划项目(2017YFB0304000,2017YFB0304001)。

摘　　要：为研究中等碱度精炼渣中Al_(2)O_(3)含量对钢洁净度和夹杂物的影响,在1873 K温度下用MgO坩埚开展了初始碱度为4、不同Al_(2)O_(3)含量的CaO-SiO_(2)-Al_(2)O_(3)-MgO顶渣与铝脱氧钢的平衡试验。结果表明,渣-钢反应后,夹杂物类型由反应前的MgO-Al_(2)O_(3)-MnS复合类转变为中心为MgO-Al_(2)O_(3),边部为MgO-Al_(2)O_(3)-SiO_(2)-CaO(-MnO)系的包裹体复合类;形貌由边界多棱角的块状和簇群状转变为边界圆滑的类球状。随着渣中Al_(2)O_(3)含量的增加,夹杂物中Al_(2)O_(3)含量显著增加,MgO含量减少,其他组分含量变化不大;夹杂物尺寸呈现增大的趋势;夹杂物数量密度增大,钢的洁净度降低。该试验条件下,当w(Al_(2)O_(3))≈20%时,夹杂物数量密度最小,钢液的洁净度最高。基于试验结果,对渣、钢的成分变化和夹杂物转变做了热力学讨论。In order to study the influence of Al_(2)O_(3)content in medium-basicity refining slag on steel cleanness and inclusions,the equilibrium experiment between CaO-SiO_(2)-Al_(2)O_(3)-MgO top slag with initial basicity of 4 and different Al_(2)O_(3)content and Al-killed steel was carried out by MgO crucible at 1873 K.The results show that after slag-steel reaction,the inclusion type changes from MgO-Al_(2)O_(3)-MnS to complex centered with MgO-Al_(2)O_(3)and surrounded by MgO-Al_(2)O_(3)-SiO_(2)-CaO(-MnO)system.The shape changes from block and cluster shape with angular boundary to near-spherical shape with smooth boundary.With the increase of Al_(2)O_(3)content in slag,Al_(2)O_(3)content in inclusions increases significantly,MgO content decreases,and other components have little change.The inclusion size tends to increase.The number density of inclusions increases which indicates that the cleanliness of steel deteriorates.Under present experimental conditions,when the Al_(2)O_(3)mass fracton is about 20%,the number density of inclusions is the lowest,and the steel cleanliness is the best.Based on the experimental results,thermodynamic analysis was done to discuss the composition change of slag and steel as well as the transformation of inclusions.

关 键 词：精炼渣 铝脱氧钢 中等碱度 Al_(2)O_(3)含量 非金属夹杂物 

分 类 号：TF769[冶金工程—钢铁冶金]