72A硬线钢丝拉拔裂纹的形成与扩展机制  

Crack Nucleation and Propagation Mechanisms in Cold-drawing of 72A Hard Wire

作　　者：牛亚然[1] 陈光[1] 赵金伟[1] 贾宁辰 刘世仁 黄一新 

机构地区：[1]南京理工大学材料科学与工程系,江苏南京210094 [2]南京钢铁有限集团公司,江苏南京210035

出　　处：《机械工程材料》2004年第8期49-51,共3页Materials For Mechanical Engineering

摘　　要：通过光学显微镜、扫描电镜和透射电镜观察,分析了72A硬线钢丝拉拔裂纹形成与扩展机制。结果表明:钢丝在拉拔过程中于表面层状非索氏体和大尺寸非金属夹杂物处形成横向裂纹源,钢丝内部游离态铁素体和夹杂物的交互作用形成裂纹扩展通道。净化钢液,消除大尺寸非金属夹杂物;优化热轧工艺,消除游离态铁素体可避免拉拔断裂。Through metallograghy SEM and TEM observation the initiation and propagation mechanism of cracks in cold-drawing of 72A hard wire was analyzed. The results showed that non-sorbite layer of surface and large dimension inclusions were the sources of transversal cracks; the compound function of free ferrite and inclusions in the wires resulted in formation of the passage through which cracks propagated. Purifying the liquid steel, optimizing the hot-rolling technology to ensure the uniformity of structure, and eliminating large dimension inclusions and free ferrite are essential methods to prevent fracture in cold drawing.

关 键 词：硬线钢丝 横向裂纹 拉拔 

分 类 号：TG142.45[一般工业技术—材料科学与工程]