Cross-slip is a thermally activated process by which screw dislocation changes its glide plane to another slip plane sharing the same Burgers vector. The rate at which this process happens is determined by a Boltzmann type expression that is a function of the screw segment length and the stress acting on the dislocation. In continuum dislocation dynamics (CDD), the information regarding the length of the screw dislocation segment and local stress state on dislocations are lost due to the coarse-grained representation of the density. In this work, a data driven approach to characterize the lost information by analyzing the discrete dislocation configurations is proposed to enable cross-slip modeling in the CDD framework in terms of the coarse-grained dislocation density and stress fields. The analysis showed that the screw segment length follows an exponential distribution, and the stress fluctuations, defined as the difference between the stress on the dislocations and the mean field stress in CDD, follows a Lorentzian distribution. A novel approach for cross slip implementation in CDD employing the screw segment length and stress fluctuation statistics was proposed and rigorously tested by comparing the CDD cross-slip rates with discrete dislocation dynamics (DDD) rates. This approach has been applied in conjunction with three cross-slip models used in DDD simulations differing mainly in the functional form of cross slip activation energy. It was found that different cross-slip activation energy formulations yielded different cross-slip rates, yet the effect on mechanical stress-strain response and dislocation density evolution was minimal for the [001] type loading.

交叉滑移是一种热激活过程，通过该过程，螺旋位错将其滑移面更改为共享相同柏格斯矢量的另一个滑移面。该过程发生的速率由玻尔兹曼型表达式确定，该表达式是螺旋段长度和作用在位错上的应力的函数。在连续体位错动力学 (CDD) 中，由于密度的粗粒度表示，有关螺型位错段长度和位错局部应力状态的信息丢失了。在这项工作中，提出了一种通过分析离散位错配置来表征丢失信息的数据驱动方法，以根据粗粒度位错密度和应力场在 CDD 框架中实现交叉滑移建模。分析表明，螺旋段长度服从指数分布，应力波动（定义为位错应力与 CDD 中的平均场应力之间的差异）服从洛伦兹分布。通过比较 CDD 交叉滑移率与离散位错动力学 (DDD) 率，提出并严格测试了 CDD 中采用螺杆段长度和应力波动统计的交叉滑移实施的新方法。这种方法已与 DDD 模拟中使用的三个交叉滑移模型结合应用，主要区别在于交叉滑移激活能的函数形式。结果发现，不同的交叉滑移活化能配方产生不同的交叉滑移率，