预测纳米多孔铜弹性模量的随机分布单胞模型

纳米多孔铜的弹性模量实测值远低于分子动力学的模拟结果，且实际韧带尺寸远大于分子动力学模拟结果。通过Python平台在ABAQUS中构建纳米多孔材料的随机分布单胞模型，基于热应力比拟方法，用多尺度均匀化方法求出均匀化弹性参数。首先，利用所提模型预测纳米多孔金的弹性模量并与实测结果进行了对比，两者的高度吻合说明所提模型的有效性。其次，预测并分析了不同体积分数下纳米多孔铜的均匀化弹性模量，发现了纳米多孔铜均匀化弹性模量随着体积分数变化的阈值现象，并从力学角度对其机理进行了解释，分析了预测结果大于实测结果的影响因素。 

Stochastic unit cell model for predicting elastic modulus of nanoporous copper

The elastic moduli of nanoporous copper measured through experiment are much lower than the simulated results from molecular dynamics. And the size of actual ligaments is larger than that used in simulation. In this paper, a stochastic unit cell model of nanoporous material is established in software ABAQUS through Python platform. Homogenized elastic parameter was calculated by multiscale homogenization method based on thermal-stress analogy method. First, the elastic modulus of nanoporous gold was predicted by the present unit cell model and compared with the experimental results. The high agreement indicates the effectiveness of the present model. Second, the model was applied to predicting the homogenization elastic modulus of the nanoporous copper under different volume fractions. The threshold phenomenon of the change of the homogenization elastic modulus of the nanoporous copper with volume fractions was revealed and the mechanism of this phenomenon was interpreted physically. Finally, the influencing factors resulting in the difference between the predicted results and the experimental data were analyzed.