基于物理的体心塑性流动规律的发展 具有温度和应变率依赖性的立方金属

是 否 +2 论坛币

k人 参与回答

经管之家送您一份

应届毕业生专属福利!

求职就业群

赵安豆老师微信：zhaoandou666

经管之家联合CDA

送您一个全额奖学金名额~ !

立即领取

感谢您参与论坛问题回答

经管之家送您两个论坛币！

+2 论坛币

摘要翻译：
在本论文中，我们首次从原子学研究中获得的数据中提取出Peierls势垒的形状及其对外加载荷的依赖关系。我们将Peierls势垒看作是位错线与垂直{111}面交点位置的二维周期函数，并带有依赖于平行和垂直于滑移方向的剪应力的可调项。这些项的泛函形式是基于最近在0K螺旋位错滑移原子模型基础上发展起来的有效屈服准则，并利用微动弹性带方法得到了两个势极之间的最小能量路径，从而得到了相应的激活势垒。所构造的Peierls势垒既正确地再现了平行于滑移方向的纯剪切所观察到的孪生-反孪生不对称现象，又正确地再现了垂直于滑移方向的剪应力效应。这一进展首次将平行于滑移方向和垂直于滑移方向的剪应力的影响引入热激活位错运动模型中。在此模型的基础上，我们提出了一个通用的屈服准则，该准则不仅包括全应力张量，还包括温度和应变率的影响。这种方法为单晶和多晶体连续介质分析的多层屈服准则和流动关系奠定了基础，其结果可以与实验观察结果进行比较。
---
英文标题：
《Development of physically based plastic flow rules for body-centered
  cubic metals with temperature and strain rate dependencies》
---
作者：
Roman Gr\"oger
---
最新提交年份：
2007
---
分类信息：

一级分类：Physics        物理学
二级分类：Materials Science        材料科学
分类描述：Techniques, synthesis, characterization, structure.  Structural phase transitions, mechanical properties, phonons. Defects, adsorbates, interfaces
技术，合成，表征，结构。结构相变，力学性质，声子。缺陷，吸附质，界面
--
一级分类：Physics        物理学
二级分类：Statistical Mechanics        统计力学
分类描述：Phase transitions, thermodynamics, field theory, non-equilibrium phenomena, renormalization group and scaling, integrable models, turbulence
相变，热力学，场论，非平衡现象，重整化群和标度，可积模型，湍流
--

---
英文摘要：
  In this Thesis we first show how the shape of the Peierls barrier and its dependence on the applied loading can be extracted from the data obtained in atomistic studies at 0 K. We consider the Peierls barrier as a two-dimensional periodic function of the position of the intersection of the dislocation line with the perpendicular {111} plane, with adjustable terms dependent on the shear stresses parallel and perpendicular to the slip direction. The functional forms of these terms are based on the effective yield criterion recently developed on the basis of atomistic modeling of the glide of screw dislocations at 0 K. The minimum energy path between two potential minima, and thus the corresponding activation barrier, is obtained using the Nudged Elastic Band method. The constructed Peierls barrier reproduces correctly both the well-known twinning-antitwinning asymmetry observed for pure shear parallel to the slip direction and the effect of shear stresses perpendicular to the slip direction. This advancement introduces for the first time the effect of both shear stresses parallel and perpendicular to the slip direction into the model of thermally activated dislocation motion. Based on this model we formulate a general yield criterion that includes not only the full stress tensor but also effects of temperature and strain rate. This approach forms a basis for multislip yield criteria and flow relations for continuum analyses in both single and polycrystals the results of which can be compared with experimental observations.
---
PDF链接：
https://arxiv.org/pdf/707.3577

扫码加我 拉你入群

请注明：姓名-公司-职位

以便审核进群资格，未注明则拒绝

分享0 收藏0 回帖

关键词：依赖性 observations Experimental Transitions Dimensional parallel 方向 位错 direction flow