高硫塑料模具钢中硫稳定性控制基础研究
Research on sulfur stability control in high sulfur plastic die steel
乔家龙 1郭飞虎 2时朋召 3刘坚锋 4杨帆 4徐李军3
作者信息
- 1. 钢铁研究总院有限公司连铸技术国家工程研究中心,北京 100081;新余钢铁股份有限公司,江西新余 338001
- 2. 钢铁研究总院有限公司连铸技术国家工程研究中心,北京 100081;东北大学冶金学院,辽宁沈阳 110819
- 3. 钢铁研究总院有限公司连铸技术国家工程研究中心,北京 100081
- 4. 新余钢铁股份有限公司,江西新余 338001
- 折叠
摘要
基于高硫塑料模具钢典型缺陷检测和MnS析出行为研究,结合热力学计算和工业试验探索了高硫塑料模具钢精炼过程硫稳定性控制手段.结果表明,MnS夹杂是裂纹产生的原因之一.MnS在1 708 K开始析出,且优先发生位错形核.MnS发生晶界形核的最快沉淀析出温度为1 573 K,并在铸坯加热过程明显长大.综合高硫塑料模具钢精炼顶渣物化性质、硫容量和硫分配比的理论研究,确定最优精炼顶渣成分范围:1.55≤(w(CaO)/w(SiO2))≤1.7、24％≤ w(Al2O3)≤28％、1.4≤(w(CaO)/w(Al2O3))≤2.3、7％≤w(MgO)≤9％和2.5％≤ ∑ w(FeO+MnO)≤4.0％.精炼顶渣成分与精炼工艺优化后,VD出站到中包钢中硫平均降低质量分数由108×10-6减少至30× 10-6,平均Als损由24.9 × 10-6减少至14.2×10-6,实现了模具钢中硫稳定性和VD至中包Als损的大幅度改善.
Abstract
Based on typical defect detection and MnS precipitation behavior of high-sulfur plastic die steel,combined with thermodynamic calculation and industrial test,the sulfur stability control means in refining process of high-sulfur plastic die steel were explored.The results show that MnS inclusion is one of the causes of cracks.MnS began to precipitate at 1 708 K,and dislocation nucleation occurred first.The fastest precipitation temperature of MnS for grain boundary nucleation is 1 573 K,and it grows obviously during the heating process of billet.Based on the theoretical study of physicochemical properties,sulfur capacity and sulfur distribution ratio of refining top slag of high-sulfur plastic die steel,the optimal refining top slag composition ranges are 1.55≤(w(CaO)/w(SiO2))≤1.7、24％≤w(Al2O3)≤28％、1.4≤(w(CaO)/w(Al2O3))≤2.3、7％≤w(MgO)≤9％and 2.5％≤∑w(FeO+MnO)≤4.0％.After the optimization of refining top slag composition and refining process,the average reduction of sulfur mass fraction from VD station to tundish was reduced from 108 × 10-6 to 30 × 10-6,and the average mass fraction of Als loss was reduced from 24.9 × 10-6 to 14.2 × 10-6.Therefore,the sulfur stability and Als loss in VD to tundish were greatly improved.
关键词
高硫塑料模具钢/MnS/析出行为/顶渣/硫/稳定性Key words
high sulfur plastic die steel/MnS/precipitation behavior/top slag/sulfur/stability引用本文复制引用
基金项目
江西省重大科研专项项目(20213AAE01009)
出版年
2024
NETL
NSTL
维普
万方数据