82B盘条表面擦伤笼口断裂原因分析与预防  

Cause analysis and prevention of 82B wire rod surface scratch and cage mouth break

作　　者：余涛 张亚君[1] 杨红来[1] 张春斌[1] 黄小山[1] 张全庆[1] YU Tao;ZHANG Yajun;YANG Honglai;ZHANG Chunbin;HUANG Xiaoshan;ZHANG Quanqing(Xinyu Iron and Steel Group Co.,Ltd.,Xinyu 338001,Jiangxi,China;Jiangxi Xinhua Metal Products Co.,Ltd.,Xinyu 338001,Jiangxi,China)

机构地区：[1]新余钢铁集团有限公司,江西新余338001 [2]江西新华金属制品有限责任公司,江西新余338001

出　　处：《江西冶金》2020年第6期29-35,共7页Jiangxi Metallurgy

摘　　要：82B盘条在进入拉拔第一道次模具前的笼口环节出现异常断裂现象,严重影响产品质量和生产节奏。通过采用光学显微镜、扫描电镜及维氏硬度对断口裂纹源处组织进行理化分析,并观察82B盘条笼口断裂处断口形貌、断口处周围情况及追溯检验82B盘条的表面质量,确定笼口断裂是由盘条打包过程中打包机压盘及打包线对盘条造成擦伤引起的。盘条擦伤处在快速加热、快速冷却及碳含量分布不均匀的条件下生成隐晶马氏体,由于隐晶马氏体强度硬度高,在盘条拉拔前笼口矫直环节,受到矫直外来作用力及在内应力作用下,造成盘条容易在此处断裂。根据分析的结果及时采取预防措施,有效的避免了打包过程中打包机压盘及打包线对盘条的擦伤。82B wire rod breaks abnormally in the cage mouth before entering the first drawing die,which has huge impact on the product quality and productivity.By means of optical microscope,scanning electron microscope and Vickers hardness,the physical and chemical analysis of the crack was carried out,the fracture shape and the surrounding conditions of the 82B wire rod were observed.On top of that,the surface quality of 82B wire rod was checked.Therefore,it was determined that the fracture of 82B wire was caused by the pressure plate of the packing machine and the abrasion of the pack thread.Under the condition of rapid heating,rapid cooling and uneven distribution of carbon content,the cryptocrystalline martensite was generated on the scratch.Because of the high strength and hardness of cryptocrystalline martensite,the wire rod was easy to fracture with the external force and internal stress applied by straightening in the cage mouth before drawing.According to the analysis,preventive measures were taken to effectively eliminate the abrasion of the wire rod caused by the pressure plate of the packer and the packing thread.

关 键 词：82B盘条 笼口断裂 隐晶马氏体 擦伤 

分 类 号：TG142.1[一般工业技术—材料科学与工程]