The mechanical response of almost pure single-crystal micro-pillars under compression exhibits a highly localized behavior that can endanger the structural stability of a sample. Recent experiments revealed that the mechanical response of a crystal is very sensitive to both the presence of a quenched disorder in the sample, and the orientation of the crystal. In this work, we study the influence of disorder and crystal orientation on the large 2-D plane strain response of a FCC crystal with three active glide planes using a very simple Eulerian plasticity model in the FE framework. Our numerical and theoretical results on clean crystal pillars suggest that a single plane or many gliding planes can be activated depending on the crystal orientation. While in the former case, the deformation is localized, leading to ductile rupture, in the latter, a complex interplay between active planes takes place, resulting in a more uniform deformation. The strain-localization can be avoided when inhomogeneities are engineered inside the crystal, or the crystal orientation is altered because of the activation of multiple slip systems, resulting in a ”patchwork” of the distribution of the slip systems.

几乎纯单晶微柱在压缩下的机械响应表现出高度局部化的行为，可能危及样品的结构稳定性。最近的实验表明，晶体的机械响应对样品中淬灭无序的存在和晶体的取向都非常敏感。在这项工作中，我们使用有限元框架中非常简单的欧拉塑性模型研究了无序和晶体取向对具有三个活动滑动面的 FCC 晶体的大二维平面应变响应的影响。我们对清洁晶柱的数值和理论结果表明，可以根据晶体取向激活单个平面或多个滑动平面。而在前一种情况下，变形是局部的，导致韧性断裂，而在后一种情况下，活动平面之间发生复杂的相互作用，导致更均匀的变形。当在晶体内部设计不均匀性时，可以避免应变局部化，或者由于多个滑移系统的激活而改变晶体取向，导致滑移系统分布的“拼凑”。