Dimoka Polyxeni, Psarras Spyridon, Kostagiannakopoulou Christine, Kostopoulos Vassilis
Department of Mechanical Engineering and Aeronautics, Applied Mechanics Laboratory, University of Patras University Campus, 26504 Patras, Greece.
Institute of Chemical Engineering Sciences, Foundation for Research and Technology Hellas (ICE-HT/FORTH), 26504 Patras, Greece.
Materials (Basel). 2019 Apr 2;12(7):1080. doi: 10.3390/ma12071080.
The present study aims to investigate the influence of multi-walled carbon nanotubes (MWCNTs) on the damage tolerance after impact (CAI) of the development of Out of Autoclave (OoA) carbon fibre reinforced polymer (CFRP) laminates. The introduction of MWCNTs into the structure of CFRPs has been succeeded by adding carbon nanotube-enriched sizing agent for the pre-treatment of the fibre preform and using an in-house developed methodology that can be easily scaled up. The modified CFRPs laminates with 1.5 wt.% MWCNTs were subjected to low velocity impact at three impact energy levels (8, 15 and 30 J) and directly compared with the unmodified laminates. In terms of the CFRPs impact performance, compressive strength of nanomodified composites was improved for all energy levels compared to the reference material. The test results obtained from C-scan analysis of nano-modified specimens showed that the delamination area after the impact is mainly reduced, without the degradation of compressive strength and stiffness, indicating a potential improvement of damage tolerance compared to the reference material. SEM analysis of fracture surfaces revealed the additional energy dissipation mechanisms; pulled-out carbon nanotubes which is the main reason for the improved damage tolerance of the multifunctional composites.
本研究旨在探讨多壁碳纳米管（MWCNTs）对非热压罐（OoA）碳纤维增强聚合物（CFRP）层压板冲击后损伤容限（CAI）发展的影响。通过添加富含碳纳米管的浸润剂对纤维预制件进行预处理，并使用一种易于扩大规模的内部开发方法，成功地将MWCNTs引入到CFRP结构中。对含有1.5 wt.% MWCNTs的改性CFRP层压板在三个冲击能量水平（8、15和30 J）下进行了低速冲击，并直接与未改性层压板进行比较。就CFRP的冲击性能而言，与参考材料相比，纳米改性复合材料在所有能量水平下的抗压强度均有所提高。对纳米改性试样进行C扫描分析得到的测试结果表明，冲击后的分层面积主要减小，而抗压强度和刚度没有降低，这表明与参考材料相比，损伤容限有潜在的提高。断口表面的SEM分析揭示了额外的能量耗散机制；拔出的碳纳米管是多功能复合材料损伤容限提高的主要原因。
