泡沫铝的压剪耦合动态本构关系和抗爆炸机理研究

A series of excellent physical and mechanical properties of aluminum foam bring it irreplaceable advantages in military vehicle anti explosion field. Because of aluminum foam’s complex microstructure, its dynamic mechanical properties is very complex, and the constitutive model and failure criterion is the key and difficult point in current study. In this study, a series of static and dynamic mechanical performance experiments and failure experiments are carried out on aluminum foam. Based on experimental results and constitutive theory, a strain rate sensitive and pressure sensitive compression/shear coupled constitutive model for aluminum foam subject to complex loading, large strains, and high pressures is presented. Based on macro and micro observation of failure experiment, damage mechanics and failure mechanics, compression/shear coupled damage evolution equation and damage related failure criterion for aluminum foam is presented. Anti-explosion experiments are carried out on aluminum foam, and the proposed constitutive model and failure criterion are applied to numerical simulation of anti-explosion experiment. By comparative analysis on experiment and simulation results, the constitutive model and failure criterion are verified, and the law and mechanism of aluminum foam anti-explosion are revealed. This project will promote the development of constitutive theory of foam materials, and provide a scientific basis for the application of foam materials in military protection. It will have important application value and scientific guiding significance in the field of military vehicle protection.

泡沫铝具有一系列优异的物理和力学性能，在军用车辆抗爆炸领域具有不可替代的优势。由于泡沫铝的复杂细观结构，它的动态力学性能非常复杂，其本构模型和破坏准则是目前研究中的重点和难点。本项目针对泡沫铝材料，开展一系列静动态力学性能实验和破坏实验；基于力学性能实验结果，以本构理论为指导建立泡沫铝在复杂应力、大变形和高压状态下的应变率相关和压力相关的压剪耦合本构模型；基于破坏实验的宏细观观测结果，以损伤力学和断裂力学为指导建立泡沫铝的压剪耦合损伤演化方程及相应的含损伤破坏准则；开展泡沫铝抗爆炸实验，采用所提本构模型和破坏准则对爆炸实验进行数值仿真，通过对比、分析实验和仿真的结果，验证所提本构模型和破坏准则的合理性，揭示泡沫铝抗爆炸的规律和机理。本项目将推动泡沫材料本构理论的发展，并为泡沫材料在军事防护上的应用提供科学依据，在军用车辆防护领域具有重要的应用价值和科学指导意义。

本项目以泡沫铝材料为研究对象，通过一系列静动态力学性能实验、爆炸试验、爆炸数值仿真、优化设计和理论分析，研究了泡沫铝的动态力学特性和爆炸防护规律。主要研究内容如下：.第一、开展泡沫铝的准静态压缩实验、压剪和拉剪耦合实验、围压实验和动态压缩实验，获取了泡沫铝的准静态压缩力学特性、压剪和拉剪耦合力学特性、三轴围压力学特性和动态压缩力学特性。第二、基于材料实验结果，给出了泡沫铝的屈服面，并与Gibson-Ashby模型、Miller模型和Deshpande-Fleck模型进行了对比，研究表明，Miller模型能够更精确的表达泡沫铝的屈服行为。第三、研究了泡沫铝的应变率敏感性，并建立了应变率敏感性公式，研究表明，泡沫铝具有一定的应变率增强特性。第四、开展了泡沫铝夹芯板爆炸试验，研究了泡沫铝夹芯板在爆炸载荷下的变形和断裂特性，研究表明，在爆炸冲击下，泡沫铝主要在压剪作用下失效，面板强度对夹芯结构的防护能力有较大影响。第五、针对泡沫铝和蜂窝铝夹芯板开展了爆炸冲击仿真，对比研究了不同夹芯结构的动态响应、变形、能量吸收和传递动能等防护性能参数，研究表明，泡沫铝芯层具有较好的吸能效果，对于特定的爆炸载荷的夹芯结构，泡沫铝有最优的基材和相对密度。第六、将泡沫铝应用于车辆底部爆炸防护组件，研究了泡沫铝的爆炸防护机理，并对泡沫铝夹芯防护组件进行了优化设计，研究表明，防护组件能够起到较好的防护效果，优化设计能够提高防护组件的爆炸防护能力。