有限变形下闭孔泡沫铝的非线性压缩行为
Nonlinear compressive behaviors of closed-cell aluminum-alloy foams at finite deformation

基于Huang（北京大学）和Wang（北京大学）的理论和热力学第二定律，研究了有限变形下闭孔泡沫铝的非线性压缩行为。通过引入内变量及内变量的演化方程，给出了有限变形下同时考虑细观结构参数和黏性效应的有效幂律势函数及相应的应力表达式。基于所提出的理论模型，通过算例讨论了细观力学方法、孔隙度和黏性效应对泡沫铝应力-应变曲线的影响规律。结果表明：模型预测与实验结果基本一致，且随着黏性系数的增大，考虑黏性效应的模型预测趋向于未考虑黏性效应时的模型预测。 Based on Huang (Peking University) and Wang (Peking University)'s theory as well as the second thermodynamic law, the nonlinear compressive behaviors of closed-cell aluminum-alloy foams were studied at finite deformation. By means of introducing the internal variable and evolution equations of internal variable, the expressions of effective power-law potentials and stresses were presented whick taks meso-structural parameter and viscosity effect into consideration. With the presented theoretical models, some numerical examples were conducted to analyze the influences of micromechanics approaches, porosity and viscosity effect on the stress-strain curves of aluminum foams. The results show that the model predictions are basically agree with the experimental result. In addition, it is found that the model predictions considering the viscosity effect tend to the model predictions without considering the viscosity effect when the viscous coefficient becomes larger. 国家自然科学基金（11472025）