基于分子动力学模拟的多晶结构微观热-力耦合行为的计算

摘要

基于分子动力学模拟，建立了一套可用于表征微观下多晶结构热-力耦合行为的算法框架。该算法的要点是将连续模型和分子模拟耦合起来，并使守恒定律在微观连续模型和原子层次上都得到满足，与利用传统的连续介质力学建立晶界与晶粒的本构方程相比，本模型中的连续流是通过原子模型准确计算得到的，从而避免了使用经验的本构方程。%A numerical method based on molecular dynamics simulations for modeling thermo-mechanical behaviors of polycrystalline materials at micro-scale is presented. The main point is, the conservation laws should be satisfied both at the continuum models and atomic levels at the micro-scale. Compared with conventional continuum mechanics, the continuum fluxes in our model are calculated through molec- ular dynamics simulations. Hence, empirical constitutive laws can be bypassed.