采用有限元数值模拟方法,研究了负泊松比蜂窝在不同冲击速度下的变形模式和能量吸收等动力学响应特性。数值模拟结果表明,在动态冲击下,负泊松比行为的产生机制与静态加载下一致,仍为孔壁的内凹和旋转,同时解释了交错排布的三角形和正方形蜂窝在中低速冲击下所表现出的缩颈现象。此外,数值模拟结果还使我们对二维负泊松比多孔材料的动态力学性能和能量吸收性能有了一定的认识,也为进一步研究三维负泊松比泡沫材料的冲击行为奠定了基础。
The deformation modes and energy absorption properties of honeycombs with a negative Poisson' s ratio under in- plane dynamic crushing were studied by means of finite element simulation in this paper. The results show that behavior mechanism of negative Poisson' s ratio under dynamic crushing is the same with that at static loading of which is the cave-in or rotation, and this explains the necking phenomena of the stagger-arranged triangle and quadratic cells during the in-plane crushing. The results provide us a certain understanding of the dynamic behavior and energy absorption property of two- dimensional cellular materials with a negative Poisson' s ratio and lay the foundation of the impact behavior of three-dimensional foam materials with a negative Poisson' s ratio.