论文部分内容阅读
为了揭示短纤维无纺布对碳纤维增强树脂基复合材料(CFRP)层板层间韧性的影响规律,测试了不同面密度(1.95、3.90、7.80和15.60 mg/cm2)和不同纤维平均长度(0.8 mm和4.3 mm)的碳纤维无纺布增韧的CFRP层板I型层间断裂韧性。实验结果表明:对于不同短纤维增韧的CFRP层板,平均长度为0.8mm的短纤维增韧效果优于平均长度为4.3mm的短纤维,并且面密度为7.8mg/cm2、厚度约为150μm、平均长度为0.8mm的碳纤维无纺布显著提高了CFRP层板的层间断裂韧性,与未改性的CFRP层板相比,其能量释放率最大可提高99%。光学显微镜观察结果表明环氧基体中长度为0.8mm的短纤维具有三维交织结构,该结构可以有效地阻止裂纹的扩展;SEM观察结果表明短纤维从环氧基体中的脱粘和拔出以及短纤维周围环氧基体的塑性变形是CFRP层板的主要增韧机制。研究结论为层板短纤维增韧技术的应用奠定了基础。
In order to reveal the influence of short fiber nonwoven fabric on the interlaminar toughness of CFRP laminates, the effects of different areal density (1.95, 3.90, 7.80 and 15.60 mg / cm2) and different fiber average length (0.8 mm and 4.3 mm) carbon fiber non-woven toughened CFRP laminar I-layer fracture toughness. The experimental results show that for different short fiber toughened CFRP laminates, short fibers with an average length of 0.8 mm have better toughening effect than short fibers with an average length of 4.3 mm, with an areal density of 7.8 mg / cm 2 and a thickness of about 150 μm , The average length of 0.8mm carbon fiber nonwoven fabric significantly improves the interlaminar fracture toughness of CFRP laminates, compared with unmodified CFRP laminates, the maximum energy release rate can be increased by 99%. The optical microscopic observation showed that the short fibers with the length of 0.8mm in the epoxy matrix had a three-dimensional interlaced structure, which effectively prevented the crack growth. The SEM observation showed that the short fibers detached and pulled out from the epoxy matrix and short The plastic deformation of the epoxy matrix around the fiber is the main toughening mechanism of the CFRP laminate. The conclusion of the study lays the foundation for the application of the technology of laminate short fiber toughening.