非对称混合多层金属夹芯结构的低速撞击极限承载和能量吸收机理研究

An asymmetric hybrid multilayer metal sandwich structure is an important new representative lightweight multifunctional structure, and open a wide range of potential and promising applications in spacecraft, aircraft, ship, high-speed train and vehicle fields. This project proposes to experimentally, analytically and numerically study the ultimate load-carrying and energy absorption mechanisms of asymmetric hybrid multilayer metal sandwich structures subjected to low-velocity impact. Drop weight impact tests are carried out to study the impact deformation and failure modes of asymmetric hybrid multilayer metal sandwich structures. According to the impact deformation modes of structures and employing the proposed yield criterion related to the time, an analytical model of the dynamic response of asymmetric hybrid multilayer metal sandwich structures subjected to low-velocity impact is developed. Combining with experimental and analytical results, the impact response process and influence factors of asymmetric hybrid multilayer metal sandwich structures are numerically studied, energy absorption distribution mechanisms of all layers are discussed for the different deformation modes, the impact deformation rules and energy absorption mechanisms of structures are revealed, the corresponding failure criteria are obtained, and the residual strengths of structures after the impact damage are forecasted. The results of the project could provide the foundation of the design and crashworthiness evaluation of asymmetric hybrid multilayer metal sandwich structures.

非对称混合多层金属夹芯结构是一类重要的新型轻质多功能结构，在航天航空、舰船、高铁、汽车等领域具有广泛应用前景。本项目拟从实验、理论和数值上研究非对称混合多层金属夹芯结构的低速撞击极限承载和能量吸收机理。通过落锤撞击实验研究非对称混合多层金属夹芯结构撞击变形和失效模式。依据结构撞击变形模式，并利用建立的与时间相关的塑性屈服条件，建立适用于低速撞击作用下非对称混合多层金属夹芯结构动态响应的理论模型。借助有限元数值分析，结合实验和理论分析结果，研究非对称混合多层金属夹芯结构的撞击响应过程及影响因素，探讨不同变形模式下各层的能量吸收分配机制，揭示结构撞击变形规律和能量吸收机理，得到相关失效准则，预报撞击损伤后结构的剩余强度。本项目研究结果可为非对称混合多层金属夹芯结构的设计与耐撞性评价提供基础。

多层金属夹芯结构是一类重要的新型轻质多功能结构，在航天航空、舰船、高铁、汽车等领域具有广泛应用前景。本项目从实验、理论和数值上研究几何非对称和多层金属夹芯结构的低速撞击承载能力和能量吸收。通过落锤撞击实验研究多层金属夹芯结构撞击变形和失效模式。利用塑性屈服条件，建立适用于低速撞击作用下几何非对称和多层金属夹芯结构动态响应的理论模型。借助有限元数值分析，结合实验和理论分析结果，研究多层金属夹芯结构的撞击响应过程及影响因素。.研究了在爆炸冲击载荷下四边固支双层矩形金属泡沫夹芯板的动态响应。得到双层夹芯板动态响应解析解的上下限及薄膜解。理论预测和数值计算结果吻合较好。.理论和数值计算研究了两端固支纤维-金属层合夹芯梁的大质量低速撞击问题。得到了两端固支纤维-金属层合夹芯梁的动态响应的解析解。构造了夹芯梁最小质量的优化设计图。.通过理论分析、实验设计和数值计算方法研究了两端固支金属泡沫填充矩形细长管的大挠度弯曲。提出了泡沫填充矩形管的塑性屈服准则。给出了横向加载下两端固支泡沫填充矩形细长管结构大挠度响应理论解。进行了两端固支铝合金泡沫填充矩形管弯曲实验和数值计算研究。理论预测和实验、数值计算结果吻合较好。