蜂窝金属夹芯板重复冲击动态响应研究

蜂窝金属及其夹芯结构是一种物理功能与结构一体化的新型轻质高强结构,广泛应用于结构轻量化与碰撞冲击防护领域。采用ABAQUS非线性有限元软件建立了蜂窝金属夹芯板(honeycomb sandwich panel,HSP)结构动态冲击数值仿真模型,数值仿真计算结果与文献实验结果吻合较好,验证了数值仿真模型的正确性。在此基础上,开展了重复冲击载荷作用下蜂窝金属夹芯板结构动态响应研究,得到了重复冲击力时程曲线、动态变形时程曲线、冲击力位移曲线以及最终挠度,分析了冲击能量、蜂窝壁厚以及上、下面板厚度分配对蜂窝金属夹芯板结构重复冲击动态响应的影响规律。研究结果表明,重复冲击载荷作用下蜂窝金属夹芯板结构上、下面板弯曲变形以及蜂窝芯层压缩变形逐渐积累,蜂窝芯层薄壁结构逐渐达到密实化,结构抗弯刚度逐渐上升,变形增量逐渐减小,结构整体能量吸收率下降。通过调节蜂窝壁厚和上、下面板厚度分配可以显著调节蜂窝金属夹芯板结构重复冲击动态响应与能量吸收性能。

Dynamic responses of honeycomb sandwich panels under repeated impacts

Honeycomb metal and sandwich structure is a new type of lightweight high-strength structural and functional composite structures,which is widely applied in structural lightweight design and impact protection.In this paper,a dynamic impact numerical model of honeycomb sandwich panel(HSP)was established by using the ABAQUS/Explicit software.The numerical calculated results are in good agreement with experimental results.On this basis,the dynamic responses of HSPs under repeated impact loads were investigated.The time histories of impact force and plastic deformation,the impact force-displacement curves as well as the permanent deflections were obtained.The influences of impact energy and the wall thickness of honeycomb cells as well as the thickness distribution of face sheet on the dynamic responses and energy absorption performances of HSPs were further performed.Numerical results show that,with the increase of impact numbers,the bending deflections of both top and bottom face sheets accumulate gradually.The compressive deformations of the honeycomb cores increase gradually and finally the densification phenomenon appears,resulting in the enhancement of flexural stiffness and the reduction of bending deformation increment as well as the decrease of the impact energy absorption.In addition,the plastic deformation accumulation and energy absorption performances of HSPs under repeated impact loads can be effectively modulated by the wall thickness of honeycomb cells and the thickness distribution of face sheet.