负泊松比点阵结构填充薄壁管轴向压缩行为及吸能特性

Axial compression behavior and energy absorption characteristics of thin-walled tube filled with negative poissons ratio lattice structure

薄壁填充结构具有轻量化、高比吸能的优点,被广泛应用于航空航天、汽车、轨道交通等工程领域。负泊松比结构在受到冲击时力学性能会逐渐增强,因此本文基于双箭头型负泊松比点阵提出一种新型薄壁填充管吸能结构,通过准静态压缩实验和有限元数值模拟方法研究了新型填充管在压缩载荷作用下的变形失效模式与力学响应。建立了平均碰撞力的理论预测模型,并通过有限元分析验证了模型可靠性,在此基础上研究了负泊松比点阵结构的细观设计参数对填充管抗压缩性能的影响规律。结果表明,填充管在压缩载荷作用下的失效模式为局部屈曲失效,相比于单一薄壁管与点阵结构,填充管具有更好的抗压缩性能;通过参数分析明确了通过增加胞元杆件壁厚和下支撑杆夹角,能显著提高填充管抗压缩性能,这将为后续负泊松比点阵填充结构的抗冲击优化设计提供重要参考。

A new type of thin-walled energy absorbing structure filled with negative Poissons ratio lattice structure is proposed.The deformation failure mode and mechanical response of the new type of filled tube under compression load are investigated by quasi-static compression experiments and finite element numerical simulation.The theoretical prediction model of the average impact force is established,with the reliability of the model verified by finite element analysis.Then,the influence of the meso-design parameters of the lattice structure with negative Poissons ratio on the compression resistance of the filled tube is studied.The results show that the failure mode of the filled tube under compression load is local buckling failure.Compared with the single thin-walled tube and lattice structure,the filled tube exhibits better compression resistance;Parameter analysis indicates clearly that the compression resistance of the filled tube can be significantly improved by increasing the wall thickness of the cell member and the included angle of the lower support rod,providing an important reference for the impact resistance optimization design of the lattice filling structure with negative Poissons ratio.