Abstract: The effect of converter end [ C ] and (TiO₂) in LF slag on converter end [Ti] and A [Ti] during LF refining process, as well as the effect of [ S] and [ N] on formation of TiN in ultra-low oxygen ([ 0 ] 10 x 10^-6) steel 20CrMoH and steel 60Si2MnA have been studied. Results showed that there were two kinds of TiN inclusion: (1) individual TiN and (2) compound TiN with core of CaS； TiN was minor in inclusions in steel 20CrMoH, but TiN accounted fbr 50% - 60% of total inclusions in steel 60Si2MnA； with increasing S content in cast billet the TiN content increased；as [Ti] was (69 -80) x 10^-6, [N] and [S] respectively decreased from (60 〜74) x 10^-6 and (30 ~35) x 10^-6  to (27 - 35) x 10^-6 and (14 -20) x 10^-6, the TiN number decreased from 4.4 -6.1 per cm² to 0.4 - 1, 1 per cm² ； and as [S] W0. 002% , there was no CaS-TiN compound inclusion precipitated in steel.

Key words: Ultra-low Oxygen, Steel 20CrMoH, Steel 60Si2MnA, TiN, Process Control

摘要： 研究了超低氧(10 x 10^-6)钢20CrMoH和60Si2MnA转炉终点[C]和LF渣(TiO₂)对转炉终点[Ti[和 LF精炼过程A[Ti]的影响，以及[S]、[ N]对TiN生成的影响。结果表明,试验钢TiN夹杂有两类：(1)单独TiN； (2)CaS为核心的复合TiN。20CrMoH钢中TiN夹杂较少,60Si2MnA钢中TiN占夹杂总量的50% ~60%。随铸坯 中S含量的增加,TiN夹杂含量增加；当[Ti]为(69~80) x10^-6,[N]、[S]分别从(60~74) x 10^-6和⑶~ 35) x 10"降至(27 ~35) x10^-6和(14~20) x 10^-6时,TiN 个数从 4.4 ~ 6.1 个/cm²降低到 0.4 ~ 1.1 个/cm²；当[S]w 0. 002%，钢中无CaS-TiN复合夹杂析出。

关键词: 超低氧 , 20CrMoH钢 , 60Si2MnA钢 , TiN , 工艺控制