连铸坯表面纵裂纹的形成与控制研究现状

Research status of the formation and control of surface longitudinal cracks during continuous casting

表面纵裂纹属于严重的铸坯质量缺陷,易在轧制过程中发生显著的扩展行为,严重影响生产效率和产品质量。国内外大量研究聚焦于如何调控连铸坯表面裂纹。本文对连铸坯典型表面纵裂纹的形成及控制方法进行了综述分析。连铸坯表面缺陷影响因素主要有钢种成分、连铸参数(结晶器冷却强度、拉速、过热度、结晶器锥度等)以及所选用保护渣的理化性能等。通过各因素间的协同调控,促进铸坯表面均匀传热和坯壳稳定生长,抑制铸坯表面纵裂纹的产生。

As a serious quality defect of continuous casting,the surface longitudinal crack easy to expand during the rolling process,which seriously affects the production efficiency and product quality.A lot of researches focus on how to control the surface crack during continuous casting.Formation and control methods of typical longitudinal cracks on the surface of continuous casting product are summarized and analyzed.The main factors affecting the surface defects of continuous casting are steel composition,continuous casting parameters(mold cooling intensity,casting speed,superheat,mold taper,etc.),and physical and chemical properties of the selected mold flux.The uniform heat transfer on the surface and the stable growth of the shell were promoted and the longitudinal cracks on the surface were suppressed by the cooperative control of various continuous casing parameters.