碳纤维复合材料曲壁蜂窝结构的力学性能强化方法研究

本项目旨在通过拓扑强化设计方法和面芯界面处理方法研究，强化超轻复合材料蜂窝结构的力学性能，并对其开展结构优化设计、制备工艺、力学性能和耐水压性表征等研究工作，以满足深海潜器对轻质高强浮力结构的迫切需求。首先，基于蜂窝曲壁拓扑强化方法，结合小单胞波纹板模压工艺和波纹板叠层固化工艺研究，设计并制备碳纤维复合材料曲壁蜂窝结构，解决现有蜂窝结构易产生弹性屈曲失效而导致平压强度不高的问题。其次，基于曲壁拓扑设计方法和面芯界面处理方法研究，解决复合材料蜂窝结构易产生界面脱粘失效而导致剪切强度较低的问题。然后，通过数值分析和实验验证的手段，研究复合材料曲壁蜂窝结构的变形机制与失效模式，揭示曲壁拓扑结构和面芯界面处理强化机理。最后，开展蜂窝结构面芯变形协同设计，减轻面芯接触处应力集中现象对蜂窝结构耐水压性能的影响，为将先进的复合材料轻质高强结构应用于深海装备领域提供理论基础和技术支撑。

The program focuses on strengthening mechanical properties of lightweight composite honeycomb structures with topology strengthening design and interface processing manufacture. The optimization design, manufacture technology, mechanical properties and water pressure resistance of carbon fiber composite curved honeycombs are researched to satisfy the urgent need of lightweight and high-strength buoyancy structure for deep-sea vehicle. Firstly, lightweight composite honeycomb structures are easy to buckling in compression load, which cause low out-of-plane compressive strength. To solve this problem, the mechanical properties of carbon fiber composite honeycomb structures are enhanced with topology method of curved wall and high quality manufacture technics of honeycombs. In addition, Interface debonding of composite honeycomb structures is the main failure mode in shear load, which lead to the low shear strength. The good methods improving the interface bonding strength of composite honeycomb structures are composite surface treatment process. Moreover, the deformation mechanism and failure mode of composite honeycomb structures are researched through experiments and numerical analysis. The strengthening mechanism of curved wall topology and honeycomb interface treatment process are revealed. At last, The cooperative design of displacement between faceplates and core of honeycomb structure is carried out to reduce the influence of stress concentration at the contact area of the faceplates and core on the water pressure resistance of composite honeycomb structures. This study provides theoretical basis and technical support for the application of advanced composite lightweight sandwich structure in the field of deep-sea equipment.