蜂巢材料具有質量輕、隔熱、吸能等特性，已廣泛應用於輕質結構工程中。常見蜂巢材料之幾何形狀，包括六邊形、圓形及橢圓等，現今有關蜂巢材料彈性挫曲理論分析，主要探討六邊形之蜂巢材料，但是六邊形蜂巢材造製作不易，其他如圓形與矩形等，可能深具商業市場潛力，故本研究使用有限元素套裝軟體ABAQUS，針對不同微觀幾何蜂巢材料平面內承受雙軸壓應力作用下，建立數值分析模型，進而探討不同微觀幾何對蜂巢材料挫曲強度之影響。首先，考慮六邊形之蜂巢材料，探討不同直桿與斜桿長度與厚度對其彈性挫曲行為之影響，在來比較不同幾何形狀，圓形、橢圓與六邊形之蜂巢材料，於相同相對密度條件下，各蜂巢材料平面內承受雙軸應力作用時，其臨界挫曲強度之優劣。
數值分析結果顯示，縮短直桿與增加直桿厚度皆將提升六邊形蜂巢材料之挫曲強度，比較此兩種不同幾何變化方式，縮短直桿較增加直桿厚度更能提升六邊形蜂巢結構之挫曲強度。另外，比較六邊形、圓形及橢圓蜂巢材料之挫曲行為發現，六邊形蜂巢材料之臨界挫曲強度最強，其次為圓形，最弱則為橢圓蜂巢材料。

Honeycombs with the characteristics of light weight, good thermal insulation and high energy absorption, have been extensively used in lightweight structural engineering. The elastic buckling of hexagonal honeycombs are commonly analyzed although they are not easily manufactured. Honeycombs with other cell geometries such as circle and ellipse can be commercially used in construction engineering. Hence, their in-plane biaxial elastic buckling strengths were theoretically analyzed by using ABAQUS to investigate the effects of different cell geometries. Here, the effects of cell-edge length and thickness on the in-plane biaxial elastic buckling strengths of hexagonal honeycombs were first studied. Next, the in-plane biaxial elastic buckling strengths of same relative-density honeycombs with circular and elliptical cells were analyzed and then compared to each other. Consequently, the microstructural efficiency of honeycombs was evaluated to find the optimal cell geometry for honeycombs with high in-plane biaxial bucking strengths.
Numerical results show that the in-plane biaxial buckling strengths of hexagonal honeycombs increase as the cell-edge length is decreased or the cell-edge thickness is increased. Moreover, the effect of cell-edge length is more dramatic than that of cell-edge thickness. In addition, numerical results on the in-plane biaxial elastic buckling strengths of honeycombs with hexagonal, circular and elliptical cell edges are compared to evaluate their microstructural efficiency. It is found that the buckling strengths of honeycombs with hexagonal cell edges are higher than those with circular and elliptical cell edges.

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