This paper presents the study on crushing response of functionally stepwise graded foam under quasi-static and dynamic compression using three-dimensional (3D) Voronoi model. A series of simulations is conducted to acquire proper computing parameters and to validate the predictability of numerical model by comparing with experiment results. Two different strategies are proposed to achieve the gradient change in relative density by changing equivalent radius and cell-wall thickness. The main focus of present paper is placed on the effect of gradation configuration on the stress-strain response, deformation propagation and energy absorption. The results show that the gradation configuration has little effect on the crushing behavior of graded foams under quasi-static compression. However, the performance of graded foam under dynamic compression could be promoted by tailoring its gradation configuration. Adopting a negative gradation is beneficial for reducing the stress at the stationary side and maximizing the energy absorption under low strain level. A positive gradation would be preferred as an energy absorber under high strain level.

本文介绍了使用三维（3D）Voronoi模型在准静态和动态压缩下对功能逐步分级泡沫的破碎响应的研究。进行了一系列仿真，以获取适当的计算参数，并通过与实验结果进行比较来验证数值模型的可预测性。提出了两种不同的策略来通过改变等效半径和孔壁厚度来实现相对密度的梯度变化。本文的主要重点放在渐变配置对应力-应变响应，变形传播和能量吸收的影响上。结果表明，在准静态压缩下，梯度结构对梯度泡沫的破碎行为影响很小。然而，通过调整其渐变配置可以提高动态压缩下的渐变泡沫的性能。采用负渐变有利于减少固定侧的应力并在低应变水平下最大程度地吸收能量。在高应变水平下，优选正渐变作为能量吸收剂。