纤维增强梯度金属泡沫夹芯复合壳的低速冲击失效及其能量吸收机理研究

Lightweight fiber-reinforced composite sandwich shells with a metal graded-foam core are new basic structural elements with extensive potential applications and have lightweight, good toughness, impact resistance and multifunctional characteristics. Based on the drop-hammer impact tests, the project would investigate the low-velocity impact response and explore the energy absorption mechanism of the fiber-reinforced composite sandwich shells with a metal graded-foam core theoretically and numerically. The dynamic failure modes are given and the corresponding analytical models are developed to predict the dynamic response. The effects of the boundary conditions, geometrical parameters, loading conditions and material properties on the impact failures and energy absorption mechanisms are analyzed. The propagation rules of the stress wave in the metal graded-foam core are revealed and the strengthening and toughing mechanisms of the fiber-reinforced composite sandwich shells with a metal graded-foam core are clarified. Further, the dynamic failure criterion of the fiber-reinforced composite sandwich shells with a metal graded-foam core is obtained. Finally, in order to provide the theoretical basis and experimental foundation for the engineering applications, the impact resistance of the fiber-reinforced composite sandwich shells with a metal graded-foam core is evaluated and the fiber-reinforced composite sandwich shells with metal graded-foam core are optimized.

轻质纤维增强密度梯度金属泡沫夹芯复合壳结构是一类具有广泛应用潜力的轻质、强韧、抗冲击、多功能一体化新型基本结构单元。本项目拟以落锤冲击实验为基础，结合理论分析和数值计算，系统地研究轻质纤维增强梯度金属泡沫夹芯复合壳的低速冲击响应及其能量吸收机制，给出其动力变形失效模式，建立其动力响应的理论模型，分析边界条件、几何参数、载荷条件和材料特性等对变形失效机理及其能量吸收机制的影响，揭示应力波在梯度金属泡沫夹芯层中的传播规律，阐明纤维增强梯度金属泡沫夹芯复合壳强韧化的物理机制，进一步得到相应的失效准则。最后，对纤维增强梯度金属泡沫夹芯复合壳的抗冲击性能进行评价和优化设计，为纤维增强梯度金属泡沫夹芯复合壳的工程应用提供理论依据和实验基础。

轻质纤维增强密度梯度金属泡沫夹芯复合结构是一类具有广泛应用潜力的轻质、强韧、抗冲击、多功能一体化新型基本结构单元。本项目以实验为基础，系统地研究了准静态和动态载荷下轻质纤维增强金属泡沫和梯度金属泡沫夹芯复合结构的变形失效和低速冲击响应，获得了其变形失效模式，建立了变形失效的理论模型，重点分析了边界条件、几何参数、载荷条件和材料特性等因素对变形失效机理及其能量吸收机制的影响，揭示了应力波在夹芯层中的传播规律，阐明了纤维增强夹芯复合结构强韧化的物理机制。进一步研究了双层密度梯度牺牲层的动态力学行为、金属泡沫夹芯结构弹道冲击失效、冲击载荷下纤维金属层合板的大挠度动力响应、准静态和低速冲击下碳纤维增强Kagome格栅结构压缩力学行为、金属蜂窝夹芯结构的低速冲击失效及能量分配机理、多级类蜂窝结构的静动态压溃失效及吸能机理、低速撞击下两端固支多层金属泡沫夹芯梁的动态响应等方面的研究，研究结果将为轻质材料与结构设计提供重要理论和技术支持。