Ensemble averaging stress–strain fields in polycrystalline aggregates with a constrained surface microstructure – Part 2: crystal plasticity
Ensemble averaging stress–strain fields in polycrystalline aggregates with a constrained surface microstructure – Part 2: crystal plasticity
复制标题
具有约束表面微观结构的多晶聚集体中的系综平均应力-应变场 - 第 2 部分：晶体塑性
DOI：
10.1080/14786430601009517
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发表时间：
2007
影响因子：
1.6
通讯作者：
O. Bouaziz
中科院分区：
文献类型：
--
作者：
A. Zeghadi;S. Forest;A. Gourgues;O. Bouaziz
本文用大规模有限元和统计方法研究了三维晶粒形貌对多晶聚集体自由表面变形的影响。对于一个给定的二维表面在z = 0含有39个晶粒与给定的晶体取向，八个三维随机多晶聚集体构造具有不同的三维晶粒形状和取向，除了在z = 0，基于原始的三维图像分析程序。它们承受整体拉伸载荷条件。采用连续晶体塑性框架，分析了自由表面z = 0处的塑性应变场。计算了自由表面塑性应变场的包络平均和方差图。在弹塑性铜晶粒的情况下，波动范围在2%和80%之间被发现在所观察到的表面从一个实现的微观结构到另一个在给定的材料点的等效塑性滑移水平。所获得的领域进行比较，预测的基础上相关联的柱状晶显微组织，经常在文献中使用。
The effect of three-dimensional (3D) grain morphology on the deformation at a free surface in polycrystalline aggregates is investigated by means of a large-scale finite element and statistical approach. For a given two-dimensional surface at z = 0 containing 39 grains with given crystal orientations, eight 3D random polycrystalline aggregates are constructed having different 3D grain shapes and orientations except at z = 0, based on an original 3D image analysis procedure. They are subjected to overall tensile loading conditions. The continuum crystal plasticity framework is adopted and the resulting plastic strain fields at the free surface z = 0 are analyzed. Ensemble average and variance maps of the plastic strain field at the observed free surface are computed. In the case of elastoplastic copper grains, fluctuations ranging between 2% and 80% are found in the equivalent plastic slip level at a given material point of the observed surface from one realization of the microstructure to another. The obtained fields are compared to the prediction based on the associated columnar grain microstructure, often used in the literature.