S型褶皱混杂夹芯结构冲击失效机理及吸能特性研究

Foldcore sandwich structure as a new type of lightweight core material, and has great potential in the field of naval aviation field. According to the specific impact load, the S pattern folded sandwich structure is proposed based on folded sandwich structure, and also the failure mechanism and energy absorption characteristics of S pattern folded sandwich structure under impact loading are studied. The content of this research can be divided in three main parts: the first aspect of work is the fabrication of carbon fiber composite innovative foldcore sandwich structures, in order to improve its bearing capacity and energy absorption efficiency. The second aspect of work is to carry experimental study on air shock wave and ballistic impact tests of S pattern foldcore hybrid sandwich structure are conducted, and also build the theoretical and numerical models for predict the dynamic mechanical properties of S pattern foldcore hybrid sandwich structure, the failure mechanism maps will be conducted and then the experimental specimens will be designed according above models. The third aspect of work is to reveal the dynamic response, energy absorption and damage failure mechanism of S pattern foldcore hybrid sandwich structure under impacting, the failure criterion of S pattern foldcore hybrid sandwich structure subjected to impacting will be established. The research of this project is of great significance to deeply understand the impact resistance of folded sandwich structure, and will provide theoretical support and scientific basis for it in the design and application of the engineering structure.

皱褶夹芯结构做为一种新型轻量化芯材结构，在航空领域具有广泛的应用前景。本项目拟依据具体冲击载荷形式，在褶皱夹芯结构的基础上发展S型褶皱混杂夹芯结构，研究冲击载荷作用下S型褶皱混杂夹芯结构毁伤失效机理及吸能特性，拟开展以下三个方面的工作：1) 设计并制备碳纤维新型皱褶混杂夹芯结构，以提高其承载效率和吸能效率。2) 进行S型褶皱混杂夹芯结构空气冲击波及弹道冲击试验，建立预报皱褶夹芯混杂结构动态力学性能的理论与数值模型。3) 揭示S型褶皱混杂夹芯结构在冲击载荷作用下的动态响应特性、吸能防护性能和毁伤失效机理，并建立相应的失效判据准则。本项目研究对深入认识褶皱混杂夹芯结构的抗冲击特性具有重要意义，并将为其在工程结构中的设计应用提供理论基础和科学依据。

复合材料褶皱夹芯结构是通过二维材料折叠而成的三维周期性空间结构，作为一种新型的夹芯结构，具有轻质、高比强度、高比刚度、芯子空间贯通及多功能潜力等优势。本项目创新性地提出基于S型褶皱芯体的多种混杂夹芯结构思想，解决棱线拐角处纤维突变的瓶颈问题，提高结构载荷质量效率。利用玻璃纤维预浸料、碳纤维预浸料、铝合金板与泡沫，通过不同铺设方式设计和制备了几种S型褶皱混杂夹芯结构。基于有限元软件建立了混杂夹芯结构数值仿真模型，嵌入相应组分材料的本构关系和损伤失效准则，分析各种结构在不同冲击载荷下的动态响应特性。根据几不同S型褶皱混杂夹芯结构冲击力学性能数值模拟结果，设计出典型的实验测试件。开展了S型褶皱混杂夹芯结构在不同冲击载荷作用下的防护性能表征工作，得到各项爆炸冲击力学性能数据和失效机理，揭示不同混杂夹芯结构形式与爆炸冲击能量吸收之间的内在机制。将实验结果与数值模型进行对比分析，进一步促进数值预报模型的完善，同时将不同形式的混杂夹芯结构分析结果反馈给结构设计和制备环节，提高了结构爆炸冲击防护性能的设计方法和制备技术。