邯钢新区热轧卷板边裂成因分析和改善

边裂是影响邯钢新区热轧卷板质量的一个重要因素。对热轧卷板边部裂纹缺陷取样,进行金相分析、扫描电镜分析、能谱分析,并对连铸板坯进行对比轧制试验,证实热轧卷板边裂是由连铸板坯角部横向裂纹引起。分析了影响板坯角部横裂的钢水成分、结晶器保护渣、结晶器冷却、二冷水等工艺因素。在此基础上,提出了改善板坯角部横裂的有效措施,即优化钢水成分、改进保护渣性能、优化二冷配水、弱化结晶器冷却等。实施以上措施后,热轧卷板边部裂纹大幅度减少。

Analysis and Improvement of Edge Cracks of Hot Roiled Coil

The edge crack is the important factor which impairs the quality of hot rolled coil.Taking sample of the edge cracks defects and analyzed them by metallurgical analysis,SEM and spectrum analysis;and comparison rolling test was made on continuous casting slab.It proved that the edger cracks are caused by the transverse crack of the slab corner.At the same time full investigations were carried out on the steel chemicals,mould powders,mould cooling and second cooling.Then effective measures were proposed to upgrade transverse corner cracks such as optimization of steel chemicals,casting mould powders,second cooling and weakening mould cooling.With above measures,the edge cracks are reduced sharply.