基于层状化电磁改性碳/双马树脂基复合材料的性能及机制研究

The rapid development of stealth technology makes comprehensive requirements of thin layer,broadband,light weight and strong absorption for radar absorbing materials.Research and development of stealth compsite with efficient microwave absorbing property and excellent mechanical property is one of the technical breakthrough points to meet the requirements.A novel method of laminated electromagnetic modifing composite is presented in this research project.Nano absorbing agent/PPESK nanofibrous functional membranes are used to modify carbon/bismaleimide composite,with the aim of improving absorbing property and toughness of the composite together.Effects of absorbing agents on microstructure,tensile strength and electromagnetic parameters of nanofibrous functional membranes are studied,determining the optimum electrospinning technology parameters.Effects of different modulation structure on mechanical properties,thermal properties and interlaminar phase morphology of the composite are investigated,and the laminated toughening mechanism of nanofibrous functional membrane is revealed.Effects of electromagnetic parameters and laminated order of hybrid nanofibrous functional membranes on absorbing properties of the composite are investigated,aiming to understand multicomponent collaborative absorbing mechanisms and explore the effective way to broaden the absorbing bandwidth of the composite.On that basis,the excellent absorbing property/load-bearing capacity integrating composite are prepared through structural optimal design.The research conclusions are expected to provide important theoretical basis and technical reserve for the preparation of stealth composite materials used for the fourth generation aircrafts and the future unmanned aerial vehicles (UAV) of our nation.

隐身技术的快速发展对雷达吸波材料提出了薄、宽、轻、强的综合要求，研制具有高效吸波性能且力学性能优异的隐身复合材料是满足这一要求的技术突破点之一。本项目提出一种层状化电磁改性复合材料的新方法，拟采用纳米吸波剂/聚芳醚纳米纤维功能膜对碳/双马复合材料进行功能化改性，旨在同步提升复合材料的吸波性能与韧性。研究吸波剂的填充对纳米纤维功能膜的微观形貌、拉伸性能及电磁参数的影响，确定静电纺丝的最佳工艺参数；考察不同调制结构对复合材料力学性能、热性能及层间相形貌的影响规律，揭示纳米纤维功能膜的层状化增韧机制；研究杂化纳米纤维功能膜的电磁参数及叠合次序对复合材料吸波性能的影响规律，揭示多组元协同吸波机制，探索拓宽复合材料吸收频宽的有效途径。在此基础上，通过结构优化设计制备具有优异吸波性能/承载能力的一体化复合材料。预期研究成果为我国四代机及未来无人作战飞机用隐身复合材料的研制提供重要的理论依据和技术储备。

隐身技术的快速发展对雷达吸波材料提出了薄、宽、轻、强的综合要求，研制具有高效吸波性能且力学性能优异的隐身复合材料是满足这一要求的技术突破点之一。本项目提出一种层状化电磁改性复合材料的新方法，将吸波剂与碳/双马复合材料的连续相双马树脂基体分离，通过间接引入的方式以静电纺丝法制备的热塑性聚芳醚树脂纳米纤维膜为载体插入到复合材料预浸料的层间，并集成在复合材料层压板的共固化成型工艺过程中。利用X射线衍射（XRD）、扫描电镜（SEM）、能谱仪（EDS）、动态力学分析（DMA）、矢量网络分析仪等手段分析了吸波剂的填充对纳米纤维功能膜的微观形貌、直径分布、电磁参数及动态力学性能的影响，重点考察了纳米纤维功能膜层间电磁改性复合材料的力学性能及吸波性能的变化规律。研究表明，聚芳醚纳米杂化纤维膜具有独特的三维网络状纳米纤维互穿结构，Fe3O4、CNTs等纳米吸波剂的负载导致杂化复合纤维表面粗糙，直径减小，并赋予其较高的介电损耗和磁损耗能力；通过界面极化及纳米吸波粒子固有的自然共振、交替共振等作用，纳米纤维功能膜在碳/双马复合材料层间的引入使其最大吸收值达到-16.85dB，低于-10 dB 的吸收频带为9.7-16.7 GHz；同时，在两相界面处呈颗粒状的双马树脂被聚芳醚树脂包裹形成连续相界面层，同步提升了复合材料的力学性能。为设计和制备兼具吸波隐身与结构承载一体化复合材料开辟了一条新的途径。