Abstract：Closed-cell aluminum foams with variable densities in the loading direction are widely used. A finite-element mode (FEM) is used to model the foam deformation and energy absorption characteristics with dynamic and quasi-static compression tests. The results show that large aluminum foam specimens with variable densities have density-dependent layered deformation characteristics, which differ from uniform-density aluminum foams. Predictions of an FEM model with a layered variable density and layered element sizes are compared with those of a conventional FEA model with uniform density and element size. The computation results show that the layered gradual deformation characteristics can be simulated by the layered models with quasi-static and dynamic compression simulation results agreeing well with experimental data. The uniform model cannot accurately predict the layered gradual deformation characteristics. The element size of the layered models influences the simulated layered gradual deformation characteristics with simulation results using the layered model with element sizes equal to the foam cell diameter agreeing best with the experimental data. These results will improve engineering designs using aluminum foam materials.
吕振华, 孙靖譞. 轴向变密度铝泡沫件的动态和静态压缩实验与有限元模拟分析[J]. 清华大学学报（自然科学版）, 2017, 57(7): 753-762.
LÜ Zhenhua, SUN Jingxuan. Dynamic and static compression tests and FEA analyses of aluminum foam specimen with variable density in the loading direction. Journal of Tsinghua University(Science and Technology), 2017, 57(7): 753-762.
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2017, Vol. 57 
