Continuum Dislocation Dynamics

位错运动作为晶体材料塑性变形过程的基本物理机制已被广泛接受，并在不同长度尺度上引入了各种基于位错的模型。虽然平均公式引入了不同的简化和近似来表示宏观材料行为，但离散位错动力学包含了每个位错的应力场，从而引入了基于物理的模拟模型。与离散模型非常接近的是一种基于位错连续体的方法，它是基于离散位错运动的直接均匀化。它的目标是位错运动的连续表示，这是直接由位错集合的物理平均产生的。因此，一个中心目标是在没有现象学拟合参数的情况下，以一般连续体方法表示三维位错相互作用和反应。我们的下一个目标是在描述中包括关键的微观结构元素，如晶界和沉淀。

Dislocation motion as the fundamental physical mechanism of plastic deformation processes in crystalline materials is well accepted and various dislocation based models have been introduced on different length scales. Whereas averaged formulations introduce different simplifications and approximations to represent the macroscopical material behavior, discrete dislocation dynamics incorporates the stress field of each dislocation and thereby introduces a physically based simulation model. In close proximity to the discrete model a dislocation based continuum approach is followed here which is based on a direct homogenization of discrete dislocation motion. It aims at a continuum representation of dislocation motion, which results directly from physical averages of dislocation ensembles. Therefore, a central objective is to represent 3D dislocation interactions and reactions in a general continuum approach without phenomenological fitting parameters. One of our next goals is to include crucial microstructural elements in the description like grain boundaries and precipitates.