• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >An experimental and computational investigation of dynamic ductile fracture in stainless steel welds.
【24h】

An experimental and computational investigation of dynamic ductile fracture in stainless steel welds.

机译：不锈钢焊缝动态延性断裂的实验和计算研究。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The high strain rate viscoplastic flow and fracture behavior of NITRONIC-50 and AL6XN stainless steel weldments are studied under dynamic loading conditions. The study is primarily motivated by interest in modeling the micromechanics of dynamic ductile failure in heterogeneous weldments. The high strain rate response of specimens machined from the parent, weld and heat-affected zones of NITRONIC-50 and AL6XN weldments is reported here on the basis of experiments conducted in a compression Kolsky bar configuration. The failure response of specimens prepared from the various material zones is investigated under high rate loading conditions in a tension Kolsky bar set-up. The microstructure of voided fracture process zones in these weldments is studied using X-ray Computed Microtomography. To model the preferential evolution of damage near the heat-affected zone, a finite deformation elastic-viscoplastic constitutive model for porous materials is developed. The evolution of the macroscopic flow response and the porous microstructure have been analysed in two distinctive regimes: pre-coalescence and post-coalescence. The onset of void coalescence is analyzed on the basis of upper-bound models to obtain the limit-loads needed to sustain a localized mode of plastic flow in the inter-void ligament. A finite element framework for the integration of the porous material response under high rate loading conditions is implemented as a user-subroutine in ABAQUS/Explicit. To address the effect of mesh sensitivity of numerical simulations of ductile fracture, a microstructural length scale is used to discretize finite element models of test specimens. Results from a detailed finite element study of the deformation and damage evolution in AL6XN weldments are compared with experimental observations.
机译：在动态载荷条件下研究了NITRONIC-50和AL6XN不锈钢焊件的高应变率粘塑性流动和断裂行为。这项研究的主要动机是对异质焊件中动态延性破坏的微观力学进行建模。根据在压缩Kolsky钢筋配置中进行的实验，在此报告了从NITRONIC-50和AL6XN焊件的母体，焊缝和热影响区加工的样品的高应变速率响应。在高负荷条件下，在张力Kolsky钢筋装置中研究了从各种材料区域制备的试样的失效响应。使用X射线计算机断层扫描技术研究了这些焊件中的空洞断裂过程区的微观结构。为了模拟热影响区附近损伤的优先演化，建立了多孔材料的有限变形弹性-粘塑性本构模型。宏观流动响应和多孔微观结构的演变已在两种不同的方式下进行了分析：聚结前和聚结后。在上限模型的基础上分析了空隙聚结的开始，以获得维持空隙间韧带中塑性流动的局部模式所需的极限载荷。在ABAQUS / Explicit中，作为用户子例程，实现了用于在高速率加载条件下集成多孔材料响应的有限元框架。为了解决延性断裂数值模拟的网格敏感性的影响，使用微结构长度标度离散化了试样的有限元模型。将对AL6XN焊件的变形和损伤演变进行的详细有限元研究结果与实验观察结果进行了比较。

著录项

  • 作者

    Kothnur, Vasanth Srinivasa.;

  • 作者单位

    Brown University.;

  • 授予单位 Brown University.;
  • 学科 Engineering Mechanical.; Engineering Materials Science.
  • 学位 Ph.D.
  • 年度 2002
  • 页码 145 p.
  • 总页数 145
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 机械、仪表工业;工程材料学;
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号