内凹负泊松比蜂窝结构的面内双轴冲击响应

利用有限元模拟方法研究了内凹负泊松比蜂窝结构的面内双轴冲击响应。用节点扰动方法建立了具有不同规则度的内凹负泊松比蜂窝结构,并将其在不同冲击速度下的变形模态、应力-应变曲线和能量耗散能力与规则蜂窝进行了对比分析。结果表明,冲击速度是内凹蜂窝结构变形模态最主要的影响因素。此外,在双轴冲击下,由于不规则度的引入,延长了应力-应变曲线的平台阶段,抑制了结构的各向异性程度,从而使结构的变形特征从局部密实转向整体密实。在能量吸收能力方面,结构的不规则性导致了密实化阶段的滞后,因此在相同的压缩程度下,其塑性耗散能低于规则模型。

In-Plane Biaxial Impact Response of Re-Entrant Auxetic Honeycomb

The in-plane biaxial impact response of a re-entrant auxetic honeycomb structure is studied by finite element simulation.A re-entrant auxetic honeycomb structure with different regularities is established by using the node perturbation method,and its deformation modes,stress-strain curves and energy dissipation capacity under different impact velocities are compared with the regular honeycomb structure.The results show that the impact velocity is the most important factor affecting the deformation mode of the honeycomb structure.In addition,due to the influence of irregularity,the plateau stage of stress-strain curve is prolonged and the degree of anisotropy of the structure is inhibited under biaxial impact,resulting that the deformation characteristics of the structure change from local compactness to overall compactness.In terms of energy absorption capacity,the irregularity of the structure leads to the lag of the compaction stage,so its plastic energy dissipation is lower than that of the regular model under the same compression degree.