摘要
介绍了天钢采用120 t BOF→LF→VD→CC工艺流程生产轴承钢GCr15的实践。在铁水磷含量较高的情况下,通过使用复吹转炉留渣与双渣吹炼法脱磷,实现了转炉终点高碳低磷出钢,C含量平均为0.32%,P含量平均为0.0095%。LF精炼过程中选用高碱度（R=7~9）的Ca O-Si O2-A12O3系精炼渣强化精炼深脱氧、脱硫,在不进行预脱硫处理工艺条件下保证了成品中[S]≤0.005%。VD真空处理后保证软吹氩时间大于20 min,镇静时间不少于10 min,以去除更多的夹杂物。最终铸坯中氧含量平均为6×10^-6,夹杂物尺寸较小,铸坯质量良好,实现了轴承钢GCr15稳定生产。
The paper introduces the practice of GCr15 bearing steel production with a process flow of 120t BOF→LF→VD→CC by Tianjin Iron and Steel Group Company Limited （TISC）. In case of high phosphorus content in hot metal, high carbon and low phosphorous tapping was realized at converter end point by adopting hot heel at combined blowing converter and dephosphorization with double slag blowing method. On average, carbon content was 0.32% and phosphorous content, 0.009 5%. In LF refining, CaO- SiO2- Al2O3 based refining slag with high basicity （R=7-9） was selected to strengthen deep deoxidation and desulfurization and ensure [S] ≤0.005% in finish product without pre-desulfurization. Time of argon soft blowing after VD treatment was ensured over 20 min and killing time no less than 15 min to remove more inclusions. Average oxygen content in final billet was 6×10^-6. The billet showed good quality with small sized inclusion. The stable production of GCr15 bearing steel was achieved.
出处
《天津冶金》
CAS
2015年第4期34-36,40,共4页
Tianjin Metallurgy
关键词
轴承钢
脱磷
精炼渣
氧含量
高碱度渣
bearing steel
dephosphorization
refining slag
oxygen content
high basicity slag
