碳纤维-泡沫铝夹芯板低速冲击响应

Low-Velocity Impact Response of Carbon Fiber-Aluminum Foam Sandwich Plate

为研究夹芯结构的低速冲击响应,以碳纤维(T700)/环氧树脂复合材料层合板为上下面板,以闭孔泡沫铝为芯层,模拟夹芯板落锤冲击时的损伤演化过程。复合材料层合板采用三维实体单元建模,基于有限元软件ABAQUS中的用户子程序VUMAT,引入三维Hashin失效准则模拟复合材料的损伤破坏;采用二次应力准则,Cohesive单元模拟黏结层的层间失效;闭孔泡沫铝芯层采用3D Voronoi细观模型建模。分析复合材料夹芯结构在落锤冲击下的损伤起始、损伤扩展和最终破坏模式,通过锤头的接触力、位移、夹芯板的内能、后面板的最大位移研究夹层结构的能量吸收情况及抗冲击特性,得出了在质量保持不变的情况下,5种芯层相对密度和厚度的耦合关系中的最优设计是芯层相对密度15.0%,厚度为10 mm,为满足实际工程中的需求提供了设计依据。

In order to study the low velocity impact response of the core-layer structure,this paper simulates the damage process of sandwich structure,that carbon fiber(T700)/epoxy composite laminates are used as the top and bottom panel,the foam aluminum is used as core layer,under impact loading of drop hammer.The composite laminates were modeled with three-dimensional solid elements,and the failure criteria of three-dimensional Hashin were introduced to simulate the damage of composite materials by the user subroutine VUMAT in the finite element software ABAQUS.The bonding layer failure between the layers was simulated with criterion of the secondary stress and cohesive unit.The aluminum foam core layer was modeled by a 3 D Voronoi mesoscopic model.By analyzing the damage initiation,damage propagation and final failure modes of composite sandwich structures under low speed impact,the progressive failure mechanism of composite materials was clarified.The contact force and displacement through the hammer head,internal energy of sandwich panel,rear panel to study the stress distribution and maximum displacement energy absorption and impact resistance of sandwich structure.The optimal design of the coupling relation between the relative density and thickness of five different core layers under the condition of a certain quality control have been obtained,which provides designed guidance for satisfying the requirements of practical engineering.