| 研究生: |
莊承鑫 Chuang, Cheng-Hsin |
|---|---|
| 論文名稱: |
具不均勻微觀構件之蜂巢材料力學性質 Mechanical Properties of Honeycombs with Plateau Borders |
| 指導教授: |
黃忠信
Huang, Jong-Shin |
| 學位類別: |
博士 Doctor |
| 系所名稱: |
工學院 - 土木工程學系 Department of Civil Engineering |
| 論文出版年: | 2002 |
| 畢業學年度: | 90 |
| 語文別: | 英文 |
| 論文頁數: | 128 |
| 中文關鍵詞: | 蜂巢材料 、不均勻斷面 、力學性質 、破壞包絡線 、挫曲強度 |
| 外文關鍵詞: | honeycomb, Plateau border, mechanical property, yield surface, buckling strength |
| 相關次數: | 點閱:100 下載:5 |
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本研究針對具不均勻微觀構件之蜂巢材料力學性質進行廣泛性之研究,首先建立一具不均勻斷面之理論模型,並利用巨觀參數相對密度 與微觀參數 定義其剖面形貌,並以樑之變形理論進行理論分析,包括楊氏模數、剪力模數、柏松比、彈性挫曲強度、塑性崩塌強度與雙軸載重之降伏包絡線,結果發現力學性質與其相對密度與微觀參數息息相關,且各力學性質隨著微觀參數變化之趨勢皆為類似,並表示存在最佳微觀結構之可能。因此,利用其數值結果建立各力學性質與相對密度之關係式,其關係式除了可以準確估計其力學性質之外,並提供最佳化微觀構件之設計圖表,以利工程實際運用所需。此研究之概念與方法將可運用於研究具不均勻微觀構件之泡沫材料力學性質。
An elastic model for honeycombs with Plateau borders is utilized to investigate its mechanical properties and the effects of solid distribution. The profile of cell edge can be defined by relative density and the volume fraction of solid contained in Plateau borders region, hence, the mechanical properties such as Young’s modulus, shear modulus, Poisson’s ratio, elastic buckling, plastic collapse strength and yield surface can be analytical examined by assuming the cell edge as a beam member. As the results, the mechanical properties of honeycombs with Plateau borders depend on both relative density and the volume fraction of solid contained in Plateau borders region. In addition, the effects of solid distribution on these mechanical properties have a similar trend which is an optimal microstructure might exist for honeycombs with Plateau borders. In order to predict these mechanical properties, the relationships between mechanical properties and relative density are proposed based on the numerical results. Furthermore, the design maps of stiffness and strength for regular honeycombs are provided to optimize the microstructure of honeycombs for engineering demand. The methods utilized in the present work still can be applied to analyze the mechanical properties of open-cell foam with non-uniform cell edges.
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