高强度低合金钢保护渣黏度和结晶温度的优化

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

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。

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 Masted 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 adiusted to increase the crystallization temperature. Since optimization the slag entrapment and crack have been properly controlled in production.