应力状态和应变率对Q690钢延性断裂行为的影响
DOI:
作者:
作者单位:

重庆大学土木工程学院

作者简介:

通讯作者:

中图分类号:

基金项目:

国家自然科学基金项目(面上项目,重点项目,重大项目)


Stress state and strain rate dependent ductile fracture behavior of Q690 steel
Author:
Affiliation:

School of Civil Engineering, Chongqing University

Fund Project:

National Natural Science Foundation of China

  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • |
  • 资源附件
  • |
  • 文章评论
    摘要:

    研究了中国Q690高强度结构钢在不同低应变率下的真实应力应变关系和延性断裂特征。加载了三种不同开口尺寸的单轴拉伸平板试件和纯剪试件,获得了广泛的应力状态。采用了试验结合数值模拟的方法确定等效塑性断裂应变、应力三轴度和罗德参数。结果表明,应力三轴度和罗德参数是控制断裂的主要影响因素。与应力相比,应变对应变率更为敏感,等效塑性断裂应变随应变率的增大而增大。此外,由于断裂前纯剪试件标距范围发生明显的变形和应力集中现象,断裂面以拉应力或拉剪应力为主。因此,纯剪试件的设计需要进一步研究。

    Abstract:

    The true stress-strain relationship and ductile fracture characteristics of Chinese Q690 high strength structural steel were investigated at different low strain rates. Sheet specimens with one un-notched and two different notch geometries were used for uniaxial tensile tests and pure shear sheet specimens were also adopted for shear tests. These specimens were loaded to obtain a wide range of stress states. A hybrid experiment-simulation approach was used to determine the equivalent plastic strain to fracture, the stress triaxiality and the Lode parameter. The results showed that the stress triaxiality and the Lode parameter are the key factors controlling fracture and that strain is more sensitive to strain rate compared to stress. It was observed that the equivalent plastic fracture strain increases with increasing the strain rate. In addition, further studies are required to design the pure shear specimens since the tensile stress or tensile-shear stress will be dominated on the fracture sections in most of pure shear tests due to the obvious deformation and stress concentration before fracture at the gauge area.

    参考文献
    相似文献
    引证文献
引用本文
分享
文章指标
  • 点击次数:
  • 下载次数:
  • HTML阅读次数:
  • 引用次数:
历史
  • 收稿日期:2019-05-13
  • 最后修改日期:2019-09-17
  • 录用日期:2019-10-14
  • 在线发布日期:
  • 出版日期: