铝蜂窝夹芯板面外剪切性能试验研究与数值模拟

Experiment and numerical simulation of out-plane shear performance of aluminum honeycomb sandwich panel

通过试验和数值模拟对铝蜂窝夹芯板的面外剪切行为和力学性能进行了研究,讨论了其失效模式,提取了典型荷载-位移曲线,分析了面板厚度、蜂窝胞元尺寸和芯层厚度对夹芯板极限承载力和吸能能力的影响。结果表明,铝蜂窝夹芯板面外剪切破坏过程大致经历弹塑性变形阶段、上面板损伤失效、芯层致密和下面板损伤失效4个阶段,呈现出整体性失效和阶段性失效两种失效模式。失效模式类型主要受到面板厚度和胞元尺寸的相对关系影响,增加面板厚度或胞元尺寸都会使破坏模式从整体性失效向阶段性失效转变,阶段性失效模式吸能能力比整体性失效模式提高。剪切强度和吸能能力随面板厚度增加而提高,随胞元尺寸增大而降低,剪切强度受芯层厚度的影响很小,夹芯板吸能能力随芯层厚度增加而提高。数值模拟与试验结果吻合程度较好,充分验证了有限元模型的可靠性。

The out-plane shear behavior and mechanical properties of aluminum honeycomb sandwich panel were studied by experiment and numerical simulation.The failure modes were discussed,and the typical load-displacement curves were obtained.The effects of face sheet thickness,cell size and core height on the pick load and energy absorption capacity of the sandwich panel were analyzed.The results show that the out-plane shear failure process of aluminum honeycomb sandwich panel goes through four stages:Elastic-plastic deformation,upper sheet damage failure,core layer density and lower sheet damage failure,and presents two failure modes:Integral failure and phased failure.The type of failure mode is mainly determined by the relative relationship between face sheet thickness and cell size.Increasing face sheet thickness or cell size will transform the failure mode from integral failure to phased failure,and the energy absorption capacity of phased failure mode is higher than integral failure mode.The shear strength and energy absorption capacity increase with the increase of face sheet thickness,but decrease with the increase of cell size.The shear strength is slightly affected by the core height,but the energy absorption capacity of sandwich panel increases with the increase of core height.The simulation results are in good agreement with the experimental results,which fully verifies the reliability of the finite element model.