论文标题
使用数据驱动的方法鉴定复杂位错网络中的错位反应动力学用于连续建模
Identification of dislocation reaction kinetics in complex dislocation networks for continuum modeling using data-driven methods
论文作者
论文摘要
金属的塑性变形涉及形成牢固连接的位错网络的位错的复杂演化。这些位错网络基于位错反应,在不同滑动系统的相互作用期间,它们可以形成连接。通过足够的基于物理的理论提取塑性变形过程中网络行为的基本原理对于晶体可塑性模型至关重要。在这项工作中,我们演示了如何通过应用基于物理的脱位网络演化理论来传输来自离散脱位动力学模拟到基于连续的配方的知识如何转移。通过使用数据驱动的方法,我们验证网络演化的依赖性速率公式。我们分析了在单轴拉伸载荷下,在高对称和非对称方向中分析了以高对称和非对称方向的面部中心单晶的不同离散脱位动力学模拟数据集。在这里,我们关注II期塑性变形期间的反应演化。我们基于物理的网络演化模型取决于塑性剪切速率和位错密度所描述的错位行进距离。我们揭示了反应动力学对晶体方向和相互作用滑移系统的活性的依赖性,可以用Schmid因子来描述。已经发现,新的反应密度的产生主要由主动滑移系统驱动。但是,产生的反应密度的沉积不一定取决于所考虑的滑移系统的滑移系统活性,即,我们观察到反应密度在不活动的滑移系统上的沉积,尤其是对于胶质菌和共面反应。
Plastic deformation of metals involves the complex evolution of dislocations forming strongly connected dislocation networks. These dislocation networks are based on dislocation reactions, which can form junctions during the interactions of different slip systems. Extracting the fundamentals of the network behaviour during plastic deformation by adequate physically based theories is essential for crystal plasticity models. In this work, we demonstrate how knowledge from discrete dislocation dynamics simulations to continuum-based formulations can be transferred by applying a physically based dislocation network evolution theory. By using data-driven methods, we validate a slip system dependent rate formulation of network evolution. We analyze different discrete dislocation dynamics simulation data sets of face-centred cubic single-crystals in high symmetric and non-high symmetric orientations under uniaxial tensile loading. Here, we focus on the reaction evolution during stage II plastic deformation. Our physically based model for network evolution depends on the plastic shear rate and the dislocation travel distance described by the dislocation density. We reveal a dependence of the reaction kinetics on the crystal orientation and the activity of the interacting slip systems, which can be described by the Schmid factor. It has been found, that the generation of new reaction density is mainly driven by active slip systems. However, the deposition of generated reaction density is not necessarily dependent on the slip system activity of the considered slip system, i.e. we observe a deposition of reaction density on inactive slip systems especially for glissile and coplanar reactions.