In the present work, simulations of mode I crack growth and plastic yielding at a crack tip in a plane strain crystal are considered. The theory of crystal plasticity is used and the analyses are made for small strains and rotations. The crack tip is considered as if it is inserted in a metallic grain (single crystal). Two types of crystals are simulated: face-centered cubic (FCC) and body-centered cubic (BCC). The crack growth zone is modeled by cohesive interfaces whose separation process is described by a cohesive zone model. The material and the cohesive surfaces have independent constitutive relations and fracture is an outcome of the deformation process. The cohesive tractions are implemented within the finite element method model through the principle of virtual work. A finite element mesh with rectangular bilinear elements is combined with cohesive elements to model the structure. BCC structures showed a greater toughness than FCC structures in the orientation tested, considering all other properties the same. Viscous properties influence on fracture—crack growth characteristics such as crack extension and time for the beginning of the growth process—were also explored and direct comparisons between the two types of crystal were made. In these cases, FCC crystals showed a greater rate dependency than BCC.

在目前的工作中，考虑了模拟I型裂纹扩展和平面应变晶体裂纹尖端塑性屈服的模拟。使用了晶体可塑性理论，并对小应变和小旋转进行了分析。裂纹尖端被认为是插入金属颗粒（单晶）中。模拟了两种类型的晶体：面心立方（FCC）和体心立方（BCC）。裂纹扩展区由内聚界面建模，其分离过程由内聚区模型描述。材料和内聚表面具有独立的本构关系，而断裂是变形过程的结果。内聚牵引力是通过虚拟工作原理在有限元方法模型中实现的。将具有矩形双线性元素的有限元网格与内聚元素组合以对结构进行建模。考虑到所有其他特性相同，BCC结构在测试的方向上显示出比FCC结构更高的韧性。还研究了粘性对断裂的影响（裂纹扩展特性，如裂纹扩展和开始生长的时间），并对两种类型的晶体进行了直接比较。在这些情况下，FCC晶体显示出比BCC更大的速率依赖性。还研究了粘性对断裂的影响（裂纹扩展特性，如裂纹扩展和开始生长的时间），并对两种类型的晶体进行了直接比较。在这些情况下，FCC晶体显示出比BCC更大的速率依赖性。还研究了粘性对断裂的影响（裂纹扩展特性，如裂纹扩展和开始生长的时间），并对两种类型的晶体进行了直接比较。在这些情况下，FCC晶体显示出比BCC更大的速率依赖性。