摘要
针对热轧低碳钢边部翘皮多发问题,借助光学显微镜和扫描电镜SEM,观察了热轧低碳钢边部翘皮的组织形貌及翘皮组织内部小黑点成分构成。结果表明,边部翘皮缺陷具有如下特征:翘皮缺陷宏观形貌成舌状长条形,距离带钢边部20-50 mm范围。将翘皮缺陷试样,垂直于轧向进行镶嵌,光镜下观察截面,翘皮根部与基体相连,翘皮组织比正常部位明显粗大,并且利用扫描电镜观察,翘皮组织内部出现MgO、MnO、Al_(2)O_(3)、SiO_(2)等氧化物质点,说明铸坯在加热前已经存在开放性缺陷,以此判断是铸坯本身存在裂纹、气泡等原始缺陷,在轧制过程中发生分层翘起,形成翘皮缺陷。低碳钢边部翘皮引发原因及发生工序,通常有两种情况,一是来自连铸过程的铸坯本身缺陷,二是在热轧工序的轧制过程产生。判断热轧翘皮缺陷产生工序及原因,可通过对比翘皮与正常基体部位组织形貌差异性及铁素体是否有明显的粗大及脱碳层来进行判断分析。
In order to solve the problem of edge warping of hot rolled low carbon steel,the microstructure of edge warping of hot rolled low carbon steel and the composition of small black spots in the structure were observed by means of optical microscope and scanning electron microscope(SEM).The results show that the edge warping defect has the following characteristics:the macro morphology of the edge warping defect is tongue like strip,20-50 mm away from the edge of the strip.The samples with warping defect were inlaid perpendicular to the rolling direction.The cross section was observed under light microscope.The root of warping defect was connected with the matrix,and the warping structure was obviously thicker than the normal part.By scanning electron microscope,MgO,Al_(2)O_(3)、SiO_(2)and other oxidation material spots appeared in the warping structure,which indicated that there were open defects in the slab before heating The original defects,such as air bubbles,occur delamination and warping in the rolling process,forming skin warping defects.There are usually two kinds of causes and processes of edge curling of low carbon steel,one is the defects of the slab itself from the continuous casting process,the other is produced in the rolling process of the hot rolling process.In order to judge the process and cause of hot rolling skin warping defect,the difference of microstructure between skin warping and normal matrix and whether there is obvious coarse and decarburized layer in ferrite can be compared.
作者
苏振军
马银龙
杨建宽
石磊
SU Zhenjun;MA Yinlong;YANG Jiankuan;SHI Lei(Technology Center,Handan Company,Hesteel Group,Hebei Key Laboratory of Advanced Steel Materials for Auto,Handan 056015,Hebei,China;Hotrolling Plant,Handan Company,Hesteel Group,Handan 056015,Hebei,China;Steelmaking Plant,Handan Company,Hesteel Group,Handan 056015,Hebei,China)
出处
《四川冶金》
CAS
2021年第5期43-45,共3页
Sichuan Metallurgy
关键词
低碳钢
边部翘皮
氧化质点
low carbon steel
edge up warping defect
oxidation point
作者简介
苏振军(1980-),男,高级工程师,现在河钢集团邯钢公司从事汽车板研发工作,E-mail:suzhenjun@hbisco.com。
