权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Materials World Network: Physically based approach for predicting and minimizing damage nucleation in metals

材料世界网络：基于物理的方法来预测和最小化金属中的损伤成核

基本信息

批准号：
43577365
负责人：
Professor Dr.-Ing. Philip Eisenlohr, Ph.D.
金额：
--
依托单位：
Max-Planck-Institut für Eisenforschung GmbH (MPIE)
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2007
资助国家：
德国
起止时间：
2006-12-31 至 2010-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/43577365?language=en
关键词：
Materials World Network Physically based

项目摘要

The ability to predict damage nucleation and evaluate whether it will lead to failure is one major goal of computational plasticity. However, most damage modeling is based upon the assumption of pre-existing flaws, and approaches developed so far predict growth rather than nucleation of damage. While heterogeneous deformation is understood to be a precursor to damage nucleation, the step from one to the other is not clearly understood. Certainly, if heterogeneous deformation is not modeled accurately, then it is unlikely that damage nucleation, or damage growth can be confidently predicted. The proposed research seeks to obtain for the first time a suitably detailed set of data from grain ensembles around damage nucleation sites to identify the corresponding mechanisms at polycrystal boundaries. Spatially resolved slip and twin system activity, crystal orientation, lattice rotations, 3D grain boundary stereology, and local surface strain during plastic deformation is measured in situ by electron channeling contrast imaging, electron backscatter diffraction, focused ion beam milling, and digital image correlation. This extensive and unique data set facilitates the evaluation of improvements in mesoscale deformation models. By complementing experimental observations with supplemental results from verified crystal plasticity finite element simulations of the respective grain ensembles new insights into the operating damage nucleation mechanism(s) are possible. Deriving appropriate damage nucleation models from this will allow to bridge from grain-scale simulations of representative volumes where nucleation is captured to continuum-scale simulations of damage growth/propagation.

预测损伤成核并评估其是否会导致失效的能力是计算塑性学的一个主要目标。然而，大多数损伤建模是基于预先存在的缺陷的假设，并且迄今为止开发的方法预测损伤的增长而不是成核。虽然不均匀变形被理解为是破坏成核的前体，但从一个到另一个的步骤并不清楚。当然，如果不均匀变形建模准确，那么它是不可能的损伤成核，或损伤增长可以自信地预测。拟议的研究旨在获得第一次从损伤成核位点周围的晶粒系综的数据，以确定相应的机制，在多晶边界适当的详细设置。空间分辨滑移和孪晶系统的活动，晶体取向，晶格旋转，三维晶界体视学，和局部表面应变在塑性变形过程中原位测量的电子沟道衬度成像，电子背散射衍射，聚焦离子束铣削，和数字图像相关。这一广泛而独特的数据集有助于评价中尺度变形模式的改进。通过补充实验观察与补充结果验证晶体塑性有限元模拟各自的晶粒系综的新见解的操作损伤成核机制（S）是可能的。由此导出适当的损伤成核模型将允许从捕获成核的代表性体积的颗粒尺度模拟桥接到损伤生长/传播的连续尺度模拟。