泡沫填充的S型褶皱复合材料夹芯板低速冲击响应特性

为了研究泡沫填充褶皱夹芯结构低速冲击响应特性与损伤机制，采用热压法制备了玻璃纤维增强S型褶皱夹芯板，并使用聚氨酯泡沫进行了填充，通过落锤试验机对夹芯板节点与基座两个位置进行了冲击试验。研究表明，冲击位置对泡沫填充褶皱夹芯板的失效模式存在影响。当冲击位置为节点时，夹芯板芯子以凸侧面曲面壁压溃断裂失效为主，泡沫的填充起到了提供力矩的作用。当冲击位置为基座时，夹芯板芯子以凹侧面曲面壁撕裂和凸侧面曲面壁压溃失效为主，夹芯板损伤沿板厚度方向扩展充分，导致冲击载荷均匀化。在相同冲击能量下，节点与基座冲击相比，夹芯板的最大载荷力提高，并且比较稳定。此外，节点载荷峰值产生的冲击位移较低于基座冲击。 

Low-speed impact response of the composite sandwich panels with S-type foldcore filled by foam

In order to study the low-velocity impact response characteristics and damage mechanism of foam filled sandwich structure with folded core, the glass fiber reinforced S-type sandwich panel with folded core was prepared by hot pressing. Sandwich panel was filled by polyurethane foam, and the impact test was carried out on two positions of sandwich panel notes and pedestal through the drop weight testing machine. The research shows that the impact position greatly affects the failure mode of the S-type sandwich panels folded core filled by foam. When the impact position is node, the core of the sandwich panel collapsing and collapsing is mainly caused by the convex side surface wall. When the impact position is node, the core of the sandwich panel collapsing and breaking is mainly caused by the convex side surface wall, and the filling of the foam plays a role in providing torque. When the impact position is the pedestal, the core of the sandwich panel is mainly caused by the tearing of the concave surface wall and the crushing failure of the convex surface wall. The damage of the sandwich panel extends fully along the thickness direction of the plate, resulting in the homogenization of the impact load. Under the same impact energy, the maximum impact load of the node is higher than that of the pedestal, and it is more stable. In addition, the impact displacement caused by the peak load of the node is lower than that of the base impact.