浆砌层合结构复合材料的冲击损伤特性研究

Brick and mortar hierarchical laminated structure is a new composite structure mimicking shell nacre. Due to its unique micro-structure, the brick and mortar laminated structure has high strength and excellent toughness, and thus shows broad application prospect in aerospace, military, civil engineering, machinery and so on. This project carries out the research for impact damage performance of brick and mortar hierarchical laminated structure by experimental research, theoretical analysis and numerical simulation. At first, the project studies the impact damage performance of the laminated structure under low velocity impact. The deformation and damage modes of tablet and mortar, and the coupling of tablet and mortar in the process of deformation and damage are investigated, and further effect of toughness enhancement mechanism such as tablet pullout and crack deflection on low velocity impact are studied. Next the project studies the impact and penetration of the laminated structure under strong impact loading. The impact damage modes of tablet and mortar are given, and then tablet pullout, damage of mortar and crack deflection between the adjacent tablets are studied. Finally, optimization design for the impact resistance performance of brick and mortar laminated structure is carried out. This project provides theoretical basis and technological reserve for structure crashworthiness and safety protection design.

浆砌多级层合结构是一种仿贝壳珍珠层的新型复合结构，由于其独特的微结构，浆砌层合结构具有极高的强度和良好的韧性，因而在航空航天、军事、民用工程及机械等领域表现出广阔的应用前景。本申请项目拟采用实验研究、理论分析以及数值模拟的手段对浆砌层合结构的冲击损伤特性进行研究。首先研究其在低速冲击载荷下的冲击损伤性能，研究砌体片层、软胶层各自的变形失效模式，考察两者在变形失效过程中的相互耦合关系，进而研究砌体片层拔出以及裂纹偏转等增韧机制对结构低速冲击性能的影响。随后研究了浆砌层合结构在强冲击载荷下的侵彻破坏，给出软胶层、砌体片层各自的冲击损伤模式，进一步研究冲击侵彻过程中片层从软胶层拔出、软胶层的损伤以及裂纹在相邻片层之间的偏转规律。最后本项目对浆砌层合结构的抗冲击性能进行了优化设计。本项目为浆砌层合结构的耐撞性及安全防护设计提供理论基础和技术储备。

具有贝壳珍珠层微观结构的浆砌层合复合材料被广泛地应用于航空航天制造以及生物工程等领域。本申请项目通过实验研究、理论分析以及数值模拟对浆砌层合结构的冲击损伤特性进行了研究。具体内容如下：.1. 浆砌层合Voronoi结构在弹丸冲击下动态冲击损伤的数值模拟：建立了一种铝/玻璃乙烯基复合材料结构的三维Voronoi模型，随后对结构在冲击载荷下的动力学响应进行了有限元分析。从最大变形、损伤分布以及耗散能量等方面评价了规则片板模型与Voronoi片板模型在弹丸冲击荷载作用下的力学性能。.2. 浆砌层合结构三点弯动态冲击损伤的实验研究与数值模拟：利用3D打印技术制备了浆砌层合结构复合材料试样，接下来采用改进的分离式Hopkinson杆实验装置进行了三点弯冲击实验，随后对复合材料模型的三点弯动态断裂行为进行了有限元数值模拟，最后讨论了硬质砖块长宽比和软质材料层厚度对模型动态断裂行为的影响。.3. 浆砌层合结构层间断裂韧性研究：采用3D打印技术制备了张开型（I型）和滑开型（II型）断裂韧性测试试样，随后运用伯努利—欧拉梁理论和柔度校准理论等计算方法得出复合材料的层间断裂韧性，最后分析了不同粘结层厚度对复合材料断裂韧性的影响。.本项目的实施为相关结构的安全防护设计提供了理论参考。