摘要
选取具有单相和双相组织特征的X80、X90直缝管,结合微观因素分析了高钢级管线钢及钢管不同方向的形变硬化行为特征。研究发现贝氏体+铁素体组织的双相钢比单相贝氏体组织的管线钢具有更好的塑性变形能力;此外,与单相组织管线钢管圆屋顶型应力应变曲线不同,双相组织管线钢管的横向应力应变曲线出现了明显的屈服平台,导致二者形变硬化指数变化规律存在差异。双相组织中含有一定比例低位错密度铁素体及制造过程环向应变引起的应变时效是产生该现象的主要原因。
The strain hardening behavior of X80 and X90 longitudinal submerged arc welding linepipe with single or dual phase micro- structure in different directions were analyzed. It is found that the pipeline steel with bainite and ferrite dual-phase microstruetnre pos- sesses better plastic deformation ability than the pipeline steel with bainite single-phase microstructure;the stress-strain curve shape of the former in the transverse direction is different from that of the latter, and it has obvious yielding platform, which leads to their differ- ence in the varying law of deformation hardening exponent. This is because there are a certain part of ferrite with low dislocation density in the pipeline steel with dual-phase microstructure and the circumferential strain produced in manufacturing process causes strain ag- ing.
出处
《西安石油大学学报（自然科学版）》
CAS
北大核心
2017年第3期99-104,共6页
Journal of Xi’an Shiyou University（Natural Science Edition）
基金
中国石油天然气集团公司科技重大专项"第三代大输量天然气管道工程关键技术研究"(编号:2012E-2801)
关键词
高钢级管线钢
形变硬化
应变时效
位错密度
high grade pipeline steel
strain hardening
strain ageing
dislocation density
作者简介
吉玲康（1966-），男，教授级高工，博士，主要从事油气输送管材基础研究及工程应用。E-mail：jilingkang2000@163．com
