本研究藉由有限元素數值分析方式，採用實體元素建立最小重複單元體之三維有限元素數值分析模型，改變微構件之曲度與變剖面，探討微構件對蜂巢材料平面外彈性挫曲行為與動態擠壓吸能行為之影響。平面外挫曲分析依施力方向，分為軸向與剪力挫曲行為，利用數值分析求得平面外彈性挫曲強度，結合平板力學之挫曲方程式，反推不同受力作用下之挫曲常數，使用線性回歸方法描述各相對密度具曲度及變剖面蜂巢材料之挫曲常數，尋獲一具最佳微結構之蜂巢材料。

此外，藉由動態分析之數值方法，改變微構件與應變速率，觀察各階段應力與應變曲線之力學行為，瞭解微結構參數 與 值，對於蜂巢材料平面外擠壓之破壞行為，將尋找具最佳微構件之蜂巢材料，提昇蜂巢心材吸能抗震之功效。

In the study, a three-dimensional representative volume element model with multi-cell honeycomb structure and appropriate periodic boundary conditions was proposed to numerically calculate the out-of-plane mechanical properties of regular hexagonal honeycombs. Then, the effects of microstructural imperfections of solid distribution in cell edges and curved cell edges on the out-of-plane elastic buckling, dynamic crushing and energy absorption of regular hexagonal honeycombs are evaluated. Two types of out-of-plane elastic buckling are considered here: compression buckling and shear buckling. The out-of-plane elastic buckling strengths of regular hexagonal honeycombs with plateau borders and curved cell edges are calculated from a series of finite element analyses. Finite element numerical results indicate that the out-of-plane compressive buckling and shear buckling strengths of regular hexagonal honeycombs are affected significantly by the solid distribution in cell edges and the curvature of cell edges. Furthermore, the corresponding elastic buckling constants for regular hexagonal honeycombs with plateau borders and curved cell edges are determined from the finite element numerical results and the theoretical expression derived from the theory of plate. Consequently, regular hexagonal honeycombs with an optimal microstructure to have a higher elastic buckling strength are obtained. In addition, the stress-strain curves of regular hexagonal honeycombs with various microstructures subjected to different strain rates are numerically obtained and compared to each other. Again, the effects of plateau borders and curved cell edges on the out-of-plane crushing strengths of regular hexagonal honeycombs are discussed.

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