60kg／m重轨断裂分析  

Fracture Analysis of 60 kg/m Heavy Rail

作　　者：周刚 刘欣 吴丽萍 陈海英 Zhou Gang;Liu Xin;Wu Liping;Chen Haiying(Manufacture Management Department Shougang Shuicheng Iron ＆ Steel（Group）Co,Ltd,Liupanshui 553028,Guizhou,China)

机构地区：[1]首钢水钢制造管理部,贵州六盘水553028

出　　处：《水钢科技》2018年第3期18-21,52,共5页Shuigang Science & Technology

摘　　要：通常人们认为钢材在进行拉拔加工时形成的表面白亮层为高温回融淬火马氏体，但是，作者在进行失效分析时发现一起完整包含基体组织、马氏体过渡层（回融马氏体＋珠光体）、马氏体层、加工硬化过渡层（马氏体＋加工硬化层）、加工硬化层（表面白亮层）的案例，并且通过电镜、显微硬度等手段证实它们是几种完全不同的组织。通过观察和分析证明造成轨道断裂的原因是火车在剧烈刹车过程中产生的高温导致的组织改变引起的。Generally, it is considered that a white bright layer on surface of steel material during drawing process is martensite melted at high temperature. But, a complex structure which consists of a matrix structure, a transition layer （melted martensite ＋ pearlite） of martensite, a martensite layer, a transition layer （martensite ＋ a work hardening layer） of work hardening, a work hardening layer （a surface white bright layer） was observed in failure analysis. It was verified by measures such as electron microscope, microhardness tester and so on that those sub-structures included in the complex structure are totally different kinds of structures. It is testified by observation and analysis that the cause of fracture of heavy rail is structure change leaded by high temperature rising from severe braking of train.

关 键 词：表面白亮层 高温回融淬火马氏体 加工硬化层 

分 类 号：TG111.91[金属学及工艺—物理冶金]