摘要
采用U型缺口试样研究了X60管线钢经5%、10%和15%的预拉伸应变后的疲劳裂纹形成寿命。结果表明:X60管线钢拉伸变形表现出显著的应变强化效应,但塑性降低;预应变可以延长疲劳裂纹形成寿命,提高疲劳裂纹形成的抗力系数和裂纹形成的当量应力门槛值;裂纹形成的断裂为穿晶解理机制,预应变可导致更多的二次裂纹。
The U-notch specimens were used to investigate the fatigue crack initiation life of X60 pipeline steel after pre-tension straining with ductile deformation of 5%, 10% and 15%. The pre-straining had apparent straining hardening effects, but decreased the plasticity of pipeline steel. The pre-straining prolonged the fatigue crack initiation life, and increased resistance coefficient and equivalent stress threshold of the fatigue crack initiation. The fractography of the fatigue crack initiation displayed cleavage facet and more second cracks after pre-training.
出处
《机械工程材料》
CAS
CSCD
北大核心
2005年第8期46-48,70,共4页
Materials For Mechanical Engineering
基金
中国石油天然气集团公司石油管力学和环境行为重点实验室基金资助项目(ZYT-0207)
关键词
管线钢
预应变
疲劳
裂纹形成
pipeline steel
pre-straining
fatigue
crack initiation
作者简介
赵新伟（1969-），男，山西平陆人，高级工程师，博士研究生。
导师：李鹤林院士
