蜂巢材料於高溫環境下承受一固定應力時，將可能發生潛變斷裂、潛變挫曲或潛變彎曲等三種不同破壞模式，當蜂巢材料具有彎曲微桿件與肥厚區域微結構缺陷時，將對蜂巢材料潛變破壞時間造成極大影響。蜂巢材料潛變及潛變挫曲已有理論解，本研究將藉由有限元素套裝軟體，探討現存潛變斷裂及潛變挫曲理論分析結果之正確性。

有限元素數值分析蜂巢材料楊氏模數與潛變速率時，採用幾何線性小變形加以計算，數值解與理論解於微結構缺陷小時，誤差皆小於5%。但線性小變形幾何處理會去除潛變破壞的可能性，於是進行數值分析潛變破壞時，改以幾何非線性大變形方式處理。結果顯示，唯有載重較小時，潛變斷裂破壞時間之理論解較接近數值解，而潛變挫曲破壞時間之理論解，不論微結構缺陷小時或載重小時，皆與數值解差異甚大。

When honeycombs are constantly loaded at high temperatures, there are three possible failure mechanisms including creep-rupturing, creep-buckling and creep-bending. Meanwhile, the effects of dual microstructural imperfections of curved cell edges and Plateau borders on failure times are drastic and have been analyzed theoretically. In this study, a commercial finite element package was employed to numerically determine the failure times of honeycombs with the dual imperfections. Then, the numerical FEA results of creep-rupturing and creep-buckling are compared to existing theoretical results to verify their accuracy.

Using geometrically linear concept in finite element numerical analyses, the differences of Young’s modulus and creep strain rate between numerical and theoretical results are smaller than 5% under small microstructural imperfections. To avoid the suppression of creep failure, geometrically nonlinear concept was used to numerically analyze the creep behavior of honeycombs with dual imperfections. Results indicate that theoretical creep-rupturing failure times are close to numerical values only if the applied stress is small. But, the differences of creep-buckling failure times between theoretical and numerical values are dramatic even applied stress or microstructural imperfections are small.

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