摘要
运用原位拉伸扫描电子显微镜的观察方法和微观取向分析手段,对比分析了2种高强度级别管线钢X100和X80的动态塑性变形行为.结果表明:X100和X80的微观组织均主要由针状铁素体、粒状贝氏体和M/A岛状组织组成;在拉伸应力的作用下,X100级管线钢的针状铁素体首先发生形变,且随着应变的增加、针状铁素体应变量的累积而导致粒状贝氏体发生形变,其氧化夹杂物成为微裂纹成核的核心,并随着拉伸应力的增加而扩展、连接并导致裂纹贯穿基体,直至失效,在发生形变后,其晶体的{111}晶面沿拉伸形变方向转动;X80级管线钢原位拉伸产生了滑移带,并发生形变,直至断裂.
X100 and X80 high grade pipeline steel dynamic plastic deformation behavior was investigated, by means of in-situ SEM and in-situ EEBSD analysis. The results show that, the microstructure of the two pipelines is mainly composed of acicular ferrite, granular bainite and M/A island. During the tensile process, acicular ferrite deforms firstly of the X100 microstructure. With the strain increase, the variable accumulation of the acicular ferrite leads to granular bainite deformation. Subsequently, inclusion nucleates micro crack nucleation core and extends with the externally applied stress increase. Micro-cracks connection leads to crack through the matrix until failure. Correspondingly, during in-situ tensile process, the slide bands of the microstructure of the X80 pipeline run through the grains and deform cooperatively till fracture. By in-situ EBSD orientation of the X100 pipe, crystals after deformation rotate along the rolling surface for the {111} plane direction along the direction of tensile deformation.
出处
《上海交通大学学报》
EI
CAS
CSCD
北大核心
2012年第9期1455-1460,共6页
Journal of Shanghai Jiaotong University
基金
省部级重大专项基金资助项目(2008A-3005)
中国博士后基金资助项目(18420006)
关键词
管线钢
塑性形变
原位拉伸
微观取向
pipeline steel
plastic deformation
in-situ stretching
orientation
