Recently, multiscale modeling frameworks combining micromechanics-based homogenization methods and atomistic simulations have been widely applied to predict the effective stiffness of particulate-reinforced composites. Although most studies demonstrated that theoretical predictions incorporating interfacial damage are necessary to explain atomistic simulation results, the microscopic origin of the interfacial damage has not been systematically analyzed in terms of interatomic potential and interfacial structure. In this study, first, we conduct a series of particle simulations of two fictitious model crystalline composites with coherent interfaces: one has a two-dimensional triangular structure described by a bead-spring model and the other has a face-centered cubic structure described by the artificial Lennard-Jones potential. By comparing the simulation results with micromechanics theory, we obtain the interfacial bonding (damage) parameter used in the homogenization method in terms of parameters at the atomistic level. Second, we study the effects of the interfacial structures (coherent/incoherent) because of lattice or crystallographic orientation mismatch on the effective properties of composites. We obtain the elastic stiffness of Si(matrix)-Ge(nanoparticle) nanocomposites with different interfacial structures (coherent/incoherent structures) using atomistic simulations and observe that nanoparticle-size-dependency occurs only for the composite with incoherent interfaces. We propose a homogenization scheme considering the pre-stress (or residual stress) and interfacial imperfection, and explain the results from Si-Ge nanocomposite simulations.

最近，结合了基于微力学的均质化方法和原子模拟的多尺度建模框架已被广泛应用于预测颗粒增强复合材料的有效刚度。尽管大多数研究表明，结合界面损伤的理论预测对于解释原子模拟结果是必要的，但对于界面损伤的微观起源，尚未从原子间电势和界面结构方面进行系统的分析。在这项研究中，首先，我们对两种具有相干界面的虚拟模型晶体复合材料进行了一系列粒子模拟：一个具有珠-弹簧模型描述的二维三角形结构，另一个具有由珠-弹簧模型描述的面心立方结构。人造Lennard-Jones势。通过将仿真结果与微力学理论进行比较，我们获得了均质化方法中基于原子级参数的界面键合（损伤）参数。其次，我们研究由于晶格或晶体学取向不匹配而引起的界面结构（相干/不相干）对复合材料有效性能的影响。我们使用原子模拟获得具有不同界面结构（相干/非相干结构）的Si（基体）-Ge（纳米颗粒）纳米复合材料的弹性刚度，并观察到纳米颗粒尺寸依赖性仅发生于具有非相干界面的复合材料。我们提出一种考虑预应力（或残余应力）和界面缺陷的均化方案，并解释Si-Ge纳米复合材料模拟的结果。