高强度钢表面裂纹产生原因分析

Cause Analysis of Producing Surface Cracks in High-strength Plate

济钢在高强度钢生产过程中,钢板表面裂纹较多。通过分析,认为钢板表面裂纹主要是由C、Cu、Ni含量,微合金元素及浇注温度、拉速、结晶器液面波动、水口浸入深度、保护渣、加热时间等因素造成的。为此,采取控制冶炼要求,建立保护渣检测机制,确保中间包钢水过热度,调整结晶器水和二冷水,优化水口结构,铸坯实行冷送或缓冷等措施,使钢板裂纹比例明显减少,裂纹率控制到了正常水平。

During the high-strength plate producing,there are many surface cracks on the plate.The occurrence of surface cracks is largely influenced by: C,Cu and Ni content,microelements,casting temperature,casting speed,mould level fluctuating,depth of submerged nozzle during casting,mould powder,and heating time and so on.Countermeasures to prevent the surface cracks are following: establishing inspection mechanism of mold powder,keeping the excessive heat of the steel liquid in the tundish propriety,adjusting cooling water of mould and secondary cooling zone,optimizing the structure of the nozzle,adopting the cold transferring way of the continuous cast slab.The surface cracks on the plate have been dramatically reduced after applying these countermeasures.