低碳钢板坯星状裂纹缺陷分析和改善

Analysis and improvement of the star-sharped crack defect on the surface of low carbon steel slab

梅山2号连铸机生产的低碳钢板坯在热轧轧制时发生大量边部与面部翘皮缺陷,板坯实物检查有星状裂纹缺陷,结合缺陷的微观分析与现场分析结果,判断为结晶器铜板腐蚀渗铜导致。通过调整铜板镀层成分、调整结晶器足辊对中精度和喷嘴喷射角度等措施进行了改善,显著减少了结晶器的异常腐蚀,2号连铸机结晶器通钢量由4~5万t提升到了10万t以上,低碳钢板坯星状裂纹缺陷得到有效控制。

A large number of warping defect occurred in the low carbon steel slab during hot rolling,which produced by 2#CC of Meishan,a lot of star-sharped crack defects were found during slab inspection.Through micro analysis and on-site tracking of defects,it is judged that the defects were caused by copper penetration of mould corroded copper plate.Some measures have been inplemented,such as adjusting composition of coating,adjusting the alignment accuracy of foot-rooler of mould,the angel and shower location of spray nozzle,the corrosion of copper plate has been improved.The steel throughput of 2#CC was increased from 40000-50000 t to more than 100000 t,and the star-sharped crack defects of low carbon steel slab were eliminated.