FASS - Physically based modelling and simulation of the mechanical behaviour of metallic thin film systems and fine grained surfaces under cyclic loading

在这个项目中，我们的目标是对多晶金属薄膜系统和微柱在循环载荷下的力学行为进行基于物理的建模和模拟。在疲劳研究中，我们将首次使用一个包括分子动力学、离散位错动力学和连续位错动力学的综合多尺度模型框架。利用这些方法，我们研究了表面和界面(晶界)与疲劳引起的位错图案和裂纹的相互作用，以了解大体积系统和微尺度元件中疲劳破坏的早期阶段。将研究集中在小样本上，可以完全模拟微结构过程，使我们能够通过比较我们的模拟和特别定制的实验来直接验证建模工作，这是该项目的重要部分。该项目的最终目标是通过建立一个针对疲劳破坏早期阶段的预测性多尺度建模框架，为抗疲劳微结构的计算设计提供物理基础。这将有利于广泛的技术应用，包括通过表面处理提高疲劳抗力和微尺度部件的疲劳。

In this project we aim at physically based modelling and simulation of the mechanical behaviour of polycrystalline metallic thin film systems and micropillars under cyclic loads. For the first time in a fatigue study we will use a comprehensive multiscale modelling framework which comprises molecular dynamics, discrete and continuum dislocation dynamics. With these methods we investigate the interplay of surfaces and interfaces (grain boundaries) with fatigue-induced dislocation patterns and cracks, in order to understand early stages of fatigue failure in bulk systems as well as in microscale components. Focusing the investigation on small samples, which are amenable to full simulation of microstructural processes, allows us to directly validate the modelling effort by comparing our simulations with specifically tailored experiments which are an important part of the project.The ultimate goal of the project is to provide physical foundations for computational design of fatigue resistant microstructures by establishing a predictive multiscale modelling framework for the early stages of fatigue failure. This will be of benefit for a vast range of technological applications including the enhancement of fatigue resistance by surface treatment and fatigue of microscale components.