Q345E钢板表面横裂纹成因分析及控制措施  

Cause analysis and control measures of surface transverse crack of Q345E steel plate

作　　者：吴涛[1] WU Tao(Tianjin Iron and Steel Group Co.,Ltd.,Tianjin 300301,China)

机构地区：[1]天津钢铁集团有限公司,天津300301

出　　处：《天津冶金》2022年第5期57-60,共4页Tianjin Metallurgy

摘　　要：天津钢铁集团有限公司在组织生产Q345E钢板过程中,发现该钢种成品钢板表面频繁出现横裂纹。为查找钢板表面裂纹的产生原因,采用扫描电镜及能谱分析仪对Q345E成品钢板以及相应连铸坯表面横裂纹缺陷部位进行了检测。本文根据扫描电镜及能谱分析仪的检测结果,以及工艺跟踪和调查情况,对Q345E钢板裂纹缺陷产生的原因进行了分析,确认该钢种成品钢板表面裂纹是由连铸坯表面裂纹所致,而连铸保护渣理化指标不合格以及结晶器冷却水流量过高是导致Q345E钢连铸坯表面横裂纹的主要原因。通过调整Q345E钢连铸保护渣理化指标并严格检验、适当降低结晶器冷却水流量等措施,使Q345E钢板、钢坯表面横裂纹得到了有效控制。In the process of Tianjin Iron and Steel Group Co.,Ltd.organizing the production of Q345E steel plate,it was found that transverse cracks frequently appeared on the surface of the finished steel plate.In order to find out the cause of production of the steel plate surface crack,scanning electron microscope and energy spectrum analyzer were used to detect the transverse cracks on the surface of Q345E finished steel plate and the corresponding continuous casting billet.According to the detection results of scanning electron microscope and energy spectrum analyzer,as well as the process tracking and investigation situation,this paper analyzes the causes of production of the cracks of Q345E steel plate,and confirms that the surface cracks of this finished steel plate are caused by the surface cracks of the continuous casting billet,while the unqualified physical and chemical indicators of mold fluxes and the excessive flow of cooling water in the mold are the main reasons for producing the continuous casting billet surface transverse cracks of Q345E steel.Through adjusting the physical and chemical indexes of Q345E steel mold fluxes also strictly inspecting,and appropriately reducing the cooling water flow of the mold,the transverse cracks on the surface of Q345E steel plate and continuous casting billet were effectively controlled.

关 键 词：Q345E钢板 表面横裂纹 保护渣 结晶器 控制措施 

分 类 号：TF777[冶金工程—钢铁冶金]