ER70S-6焊丝钢拉拔脆断原因分析  

Analysis on the Cause of Drawing Brittle Fracture for ER70S-6 Welding Wire Steel

作　　者：高峰[1] 寇沙沙[1] 王亚男 刘莉[1] 

机构地区：[1]内蒙古包钢钢联股份有限公司技术中心,内蒙古包头014010

出　　处：《包钢科技》2018年第1期58-61,95,共5页Science & Technology of Baotou Steel

摘　　要：ER70S-6焊丝钢自Φ5.5mm预冷拔至Φ1.2mm,在拔至Φ1.3mm时出现脆断现象,其中脆断部分均为笔尖状断口。通过金相、化学成分、力学性能及扫描电镜检测分析,焊丝钢脆断的主要原因是成分偏析及轧制过程中冷速过快造成硬质块状马氏体的产生,硬质块状马氏体组织在拉拔过程中因不随基体变形在其周围产生大量裂纹,变形较大时发生脆断。The cold drawing of ER70S -6 welding wire steel is from Фb5.5 mm to Ф1. 2 mm, and the brittle fracture occurs when drawing to epl. 3 mm, and all fractures are pencil -tip shaped. Through the test and analysis of metallograph- ic, chemical composition, mechanical properties and scanning electron microscope, the main cause of brittle fracture is the hard massive martensite produced by the composition segregation and the excessive cooling rate during the rolling process. In the process of drawing, hard massive martensitic structure does not change with the deformation of the matrix and pro- duces a large number of cracks around it, and brittle fracture occurs when the deformation is large.

关 键 词：焊丝钢 脆性断裂 硬质马氏体 笔尖状断口 

分 类 号：TG422.3[金属学及工艺—焊接]