新型多级负泊松比蜂窝超材料设计、动态力学行为及吸能机理

As automobiles and aerospace vehicles are tending to lightweight, low energy consumption, high speed and high reliability, there is an urgent need for high performance lightweight materials with the characteristics of ultralight, high strength and high impact resistance. By combining the advantages of hierarchical structure and negative Poisson’s ratio structure, this project will creatively design and fabricate a new type of high performance ultralight hierarchical honeycomb metamaterials with negative Poisson’s ratio and tailorable energy absorption based on additive manufacturing technology. An innovation configuration design method for hierarchical honeycomb metamaterials with negative Poisson’s ratio will be proposed, the rate-dependent characterization method and model for key mechanical and energy absorption properties of novel hierarchical honeycomb metamaterials with negative Poisson’s ratio will be developed, the mechanisms of failure, energy absorption and negative Poisson's ratio will be revealed, and an integrated optimization design method of lightweight, load-bearing and energy absorption for the sandwich structure of novel hierarchical honeycomb metamaterials with negative Poisson’s ratio will be proposed. This project will provide novel design method and technical foundation for the significant demand of high performance lightweight materials in the fields of aerospace, transportation, national defense, etc.

随着汽车、航空航天飞行器等向着轻量化、低能耗、高速、高可靠性方向发展，迫切需求超轻高强和高效抗冲击的高性能轻量化材料。本项目拟结合多级结构和负泊松比结构的优势，并基于增材制造技术，创新性地设计和制备吸能性能可调控的新型高性能超轻多级负泊松比蜂窝超材料。拟提出多级负泊松比蜂窝超材料的创新构型设计方法，建立新型多级负泊松比蜂窝超材料关键力学与吸能性能的率相关表征方法及模型，揭示其失效机理、吸能机理和负泊松比效应产生机理，并建立适用于新型多级负泊松比蜂窝超材料夹芯结构的轻质-承载-吸能一体化优化设计方法。本项目的研究将为航空航天、交通运输和国防军工等领域对高性能轻量化材料的重大需求提供新的设计方法和技术支撑。

随着汽车、航空航天飞行器等向着轻量化、低能耗、高速、高可靠性方向发展，迫切需求超轻高强和高效抗冲击的高性能轻量化材料。本项目首先系统研究了边长型多级蜂窝和节点型多级蜂窝的变形模式、力学性能和吸能特性。然后，结合边长型和节点型多级蜂窝的拓扑构型特征和构造方法，创新性地提出了一种混合型多级蜂窝拓扑构型设计方法，并基于该设计方法构造获得了多种混合型多级蜂窝新构型。最后，综合采用实验、理论和数值模拟方法研究了混合型多级蜂窝的准静态和动态力学行为，探索了多级结构参数对混合型多级蜂窝力学及吸能特性的影响。研究发现，混合型多级蜂窝具有负泊松比特性，同时可通过改变多级结构参数实现大范围调控混合型多级蜂窝的力学和吸能性能；并且，与具有相同质量的边长型和节点型多级蜂窝相比，混合型多级蜂窝的可设计性及吸能性能明显增强。本项目研究成果可为航空航天、交通运输和国防军工等领域对高性能轻量化材料的迫切需求提供新的设计方法、理论基础和实验依据。