高强度低合金钢保护渣黏度和结晶温度的优化

连铸时结晶器保护渣的黏度、结晶温度会对钢坯质量产生较大影响,采用旋转柱体法、黏温曲线分析法并结合扫描电子显微镜,研究了马鞍山钢铁股份有限公司3种不同保护渣的黏度、结晶温度。结果表明,马钢二炼钢厂生产Q420B铁塔用角钢的结晶器保护渣1 300℃时黏度0.298 Pa.s,结晶温度约1 180℃,为三者中最低。为降低卷渣情况和提高钢材质量,将黏度提高到0.35 Pa.s左右,并适当调节碱度使结晶温度升高,生产中卷渣及裂纹情况得到了较好的控制。

Optimization of viscosity and crystallization temperature for high-strength low-alloy steel mold flux

The viscosity and crystallization temperature of mold flux have a greater impact on the quality of continuous casting billet.The viscosity and crystallization temperature of the three different mold fluxes of Masteel are studied by rotating cylinder method,viscosity-temperature curve method and SEM.The results show that viscosity and crystallization temperature of Masteel’s mould fluxes used in production of steel Q420B are lowest among the three mold fluxes: η=0.298 Pa·s,T=1 175 ℃.To reduce the slag entrapment and improve the quality of steel,the viscosity of the flux is increased to about 0.35 Pa·s and the basicity is also appropriately adjusted to increase the crystallization temperature.Since optimization the slag entrapment and crack have been properly controlled in production.