精炼渣对SUS444铁素体不锈钢中夹杂物的影响  

Influence of refining slag on the inclusions in SUS444 ferrite stainless steel

作　　者：杨宏伟[1] 苏丽娟[1] 李光强[1] 陈兆平[2] 皮朝辉 周耀[1] 

机构地区：[1]武汉科技大学钢铁冶金及资源利用省部共建教育部重点实验室,湖北武汉430081 [2]宝山钢铁股份有限公司研究院,上海201900

出　　处：《炼钢》2014年第4期42-46,51,共6页Steelmaking

摘　　要：在1873K，MgO坩埚内进行了VOD精炼渣与SUS444铁素体不锈钢之间的脱氧平衡试验，考察了精炼渣对不锈钢中T．O含量及夹杂物组成、数量和尺寸分布的影响。结果表明，脱氧终点钢中硼（T．O）=0．0063％～0．0074％，提高精炼渣碱度，降低渣中Al2O3的活度，有利于降低钢中T．O含量。精炼渣碱度增加，试样中单位面积夹杂物的个数及夹杂物的平均面积分数都减小。降低渣中A1203含量，夹杂物平均粒径也降低。加入脱氧合金后，钢中夹杂物主要为A1203、MgO·Al2O3及含有少量SiO2、MnO的复合氧化物；钙处理后，钢中夹杂物主要为球形的MgO·Al2O3-CaO。随着精炼渣中a（MgO）／a（Al2O3）的增加，MgO·AlzQ夹杂物中xMgo／xAl2O3随之增加。根据试验，R=3．5、w（Al2O3）=10％、w（MgO）=10％、w（CaF2）：5％的精炼渣具有良好的精炼效果。The equilibrium experiment between VOD refining slag and SUS444 ferrite stainless steel was carried out in the MgO crucibles at 1 873 K. The influence of refining slag on the total oxygen content in stainless steel and the composition, quantity and size distribution of inclusions were investigated. It is concluded that the mass fraction of T. O in the deoxidized steel sample ranged from 0. 006 3 % - 0. 007 4 %. The T. O content in the steel decreased with the increasing of refining slag basicity and the decreasing of A1203 activity in the slag. With the increasing of basicity of refining slag, the number of inclusions per unit area as well as the average area fraction of inclusions in the steel sample decreased during the refining process. The mean particle size of inclusions reduced with the decreasing of Al2O3 content in the slag. After adding the deoxidizing alloy, the inclusions in the sample were Al2O3 and MgO·Al2O3 and complex oxides containing a small amount of SiO2 and MnO. After calcium treatment, the main inclusions in steel were spherical MgO·Al2O3-CaO. The mole ratio of MgO to Al2O3 in the MgO·Al2O3 inclusions,xMgo/xAl2O3, increased with increasing the activity ratio of MgO to Al2O3 in the refining slag,a（MgO）/a（Al2O3）. By present experiments, the refining slag, which the composition wasR=3.5, w（A1203） = 10 %, w（MgO） = 10 G, w（CaF2） =5 %, had a good refining effect.

关 键 词：VOD精炼渣 铁素体不锈钢 脱氧 夹杂物 

分 类 号：TF764.1[冶金工程—钢铁冶金]