缝合碳纤维/泡沫夹芯复合材料损伤阻抗及损伤容限性能

Damage Resistance and Damage Tolerance Performance of Stitched Carbon Fiber/Foam Sandwich Composites

通过真空辅助树脂传递模塑成型工艺(VARTM)技术制备了缝合和未缝合碳纤维/泡沫夹芯复合材料,并进行了低速冲击和冲击后压缩实验,利用深度测量仪检测冲击后的表面凹坑深度。使用Origin软件拟合出了表征损伤阻抗性能的冲击能量-凹坑深度曲线及表征损伤容限性能的凹坑深度-剩余压缩强度曲线。以未缝合复合材料为对比,发现缝合能有效提高碳纤维/泡沫夹芯复合材料的损伤阻抗性能及损伤容限性能。缝合及未缝合碳纤维/泡沫夹芯复合材料的损伤阻抗及损伤容限曲线上均存在拐点,并且损伤阻抗的拐点位置和损伤容限的拐点位置具有一致性。拐点之前,泡沫夹芯板以基体裂纹和层间分层损伤为主;拐点之后,出现了纤维断裂损伤。

The stitched and unstitched carbon fiber/foam sandwich composites were prepared by vacuum assisted resin transfer molding(VARTM) process,and low-velocity impact and post-impact compression experiments were carried out.The depth of the surface pits after impact was measured by a depth measuring instrument.The Origin software was used to fit the impact energy-pit depth curve that characterizes the damage resistance performance and the pit depthresidual compressive strength curve that characterizes the damage tolerance performance.Taking the unstitched composites as comparison,it is found that stitching can effectively improve the damage resistance performance and damage tolerance performance of carbon fiber/foam sandwich composites.There are inflection points on the damage resistance and damage tolerance curves of stitched and unstitched carbon fiber/foam sandwich composites,and the positions of the inflection points of the damage resistance and damage tolerance are consistent.Before the inflection point,most damage of foam sandwich panels is matrix cracks and interlayer delamination damage.After the inflection point,fiber fracture damage occurs.