Abstract: Through 3 heats IF steel of 210 t RH refining process test, the effect of titanium-adjusted time on cleanliness of IF steel in RH refining process is studied by scanning electron microscopy. The results indicate that titanium adjustment after adding aluminum for 2,4 and 6 min, the average N content in molten steel at RH end is 26. 7 x 10^-6, 23. 6 x 10^-6 and 27. 4 x 10^-6 , respectively. When the oxygen blowing amount for heating,the oxygen consumption is 30 〜40 m³ and the average initial oxygen content in liquid of RH is 579 x 10^-6, the T[O] is 70. 3 x 10^-6 at the RH end； When the oxygen blowing amount for heating, the oxygen consumption is 75 ~ 90 m³ and the average arrival oxygen of RH is 669 x 10^-6, the T[O] is 109. 2 x 10^-6 at the RH end. The T[O] at the RH end shows an increase trend with the increase of oxygen activity before adding aluminum. The quantity density of inclusions with 5μm equivalent diameter in steel is 9. 32 /mm² when adjusted Ti alloy after adding aluminum 6 min, it is lowest.

摘要： 通过在210 t RH精炼IF钢3个浇次的试验，采用扫描电镜详细研究了RH精炼过程中调Ti时机对IF钢洁净度的影响。结果表明，加Al后2、4、6 min调Ti，RH结束时钢液中的N含量平均分别为26.7×10^-6、23.6×10^-6、27.4×10^-6。当吹氧升温所耗氧气量在30~40 m³，RH到站氧平均为579×10^-6时，RH结束T［O］为70.3×10^-6，当吹氧升温氧耗量在75~90 m³，RH到站氧平均为669×10^-6时，RH结束T［O］为109.2×10^-6。随着加Al前氧活度增加，RH结束时T［O］总体呈增加趋势。加Al后6 min调Ti钢中5 μm当量直径夹杂物数量密度最低为9.32个/mm²，夹杂物数量密度最低。