异形坯表面纵裂纹产生原因及控制措施  

Analysis of the cause and Preventive Measures for the surface longitudinal Cracks of Beam Blank

作　　者：梁军 孙彪 LIANG Jun;SUN Biao

机构地区：[1]马钢股份公司长材事业部,安徽马鞍山243000

出　　处：《安徽冶金科技职业学院学报》2021年第3期34-37,共4页Journal of Anhui Vocational College of Metallurgy and Technology

摘　　要：利用金相和扫描电镜对异形坯表面纵裂纹进行分析,裂纹内表面覆盖了一层氧化铁,在距离表面0.67 mm以内区域有保护渣成分,再往内部除氧化铁外,未见有保护渣成分,说明裂纹是在结晶器内产生的、二冷段里扩展的。通过对钢水成分、结晶器冷却水、结晶器液面波动、保护渣成分、钢水过热度、拉速、二次冷却水等工艺参数的优化调整,异形坯表面纵裂纹的发生率明显降低,纵裂纹指数由80 mm/m降至≤5 mm/m。Metallography and electron microscopy were used to analyze the longitudinal cracks on the surface of Beam Blank.The results showed that layer of iron oxide was covered inside the crack,and there was Mould powder component within 0.67 mm of the surface.No mould power component was found inside the crack,These phenomena indicating that the crack was originated in the mold and Expanded in the secondary cooling section.By optimizing and adjusting the process parameters such as steel composition,mold cooling water,mold surface fluctuation,slag composition,steel superheat,casting speed and secondary cooling water,the incidence of longitudinal cracks on the surface of beam blank is obviously reduced,and the longitudinal crack index is reduced from 80 mm/m to less 5 mm/m.

关 键 词：异形坯 纵裂纹 控制措施 

分 类 号：TF771.2[冶金工程—钢铁冶金]