臺灣博碩士論文加值系統

本研究主要針對多孔材之複合材料三明治結構進行衝擊實驗與衝擊模擬，探討多孔材核芯對三明治結構的衝擊吸能效應與衝擊物受力情形。
過去三明治結構件，其主要核芯材料可分為，以金屬為主的金屬發泡，熱固性塑膠為主的蜂巢式以及熱固性發泡，因其加工方式，造成可塑性不大，因此本文利用可塑性較高的熱塑性發泡替換核芯素材，配合多種複合材料疊層角度，進行探討複合材料多孔材三明治結構。
本文主要應用有限元素法與ASTM D7136規範進行模擬與實驗之可行性驗證，在有限元素法方面，應用有限元素分析套裝軟體ANSYS/LS-DYNA進行動態模擬分析，在實驗方面，配合高速攝影機之動態攝影進行落錘式衝擊實驗。探討新三明治結構的核芯密度、發泡基材與複合材料疊層角度對衝擊吸能效應與衝擊物在衝擊瞬間所承受的傷害影響。研究結果顯示新三明治結構可有效減低衝擊球在瞬間接觸時之應力，降低瞬間傷害，而在改變堆疊複合材料疊層角度順序上，其受到之衝擊影響並未有顯著差異性。

This paper studies the impact resistance behavior of the composite sandwich structures with foam cores. The foam cores used in this research were made of the thermoplastic materials, such as Ethylene Vinyl Acetate Copolymer, (EVA), to replace the thermosetting foam.
This research had two objective, one is the simulation and the other is drop test. The simulation was performed by using ANSYS/LS-DYNA transient dynamic finite element analysis and the experiments was performed with the high-speed camera to shoot on all of the drop test processes. This paper was used the two methods to explore the sandwich structure deformation, energy absorption and the impactor reaction force.
The results show that the sandwich structures not only possess impact resistance and energy absorption but also effectively reduce the instant backlash suffered injuries on impactor.

封面內頁
簽名頁
授權書 iii
中文摘要 iv
Abstract v
誌謝 vi
目錄 vii
圖目錄 x
表目錄 xiv
第一章 緒論 1
1.1 研究背景 1
1.2 研究動機 2
1.3 研究目的 3
1.4 研究方法 4
1.5 研究流程 7
第二章 參考文獻 9
2.1 發泡技術回顧 9
2.2 複合材料衝擊 10
2.3 三明治結構衝擊 11
2.4 ANSYS/LS-DYNA Explicit Solver顯性解法 13
2.5 零能模式（Hourglassing） 15
第三章 研究方法 17
3.1 複合材料多孔材三明治製程 18
3.2 衝擊實驗 24
3.2.1 衝擊平台 24
3.2.2 InstruNet擷取器與LP-10F位移計 26
3.2.3 CASIO EXILIM Pro EX-F1高速攝影機 28
3.3 有限元素法之衝擊分析 30
3.3.1 元素介紹 31
3.3.2 材料性質 34
3.3.3 模型建立 40
3.3.4 邊界條件 41
3.4 開孔式泡棉與閉孔式泡棉之緩衝差異 43
3.5 能量吸收計算 43
第四章 結果與討論 45
4.1 複合材料層板衝擊實驗與CAE模型驗證 45
4.2 開孔式泡棉與閉孔式泡棉衝擊實驗 48
4.3 多孔材複合材料三明治結構衝擊實驗 50
4.3.1 密度與緩衝性之衝擊實驗 50
4.3.2 複合材料疊層順序影響之衝擊實驗 58
4.4 電腦輔助工程模擬 65
4.4.2 密度與緩衝性之衝擊模擬 65
4.4.2 複合材料疊層順序影響之衝擊模擬 75
4.5 複合材料層板與三明治結構之關係 82
4.6 三明治結構之實驗與模擬比較 83
4.6.1 不同密度多孔材核芯之衝擊實驗與模擬比較 83
4.6.2 不同疊層角度之衝擊實驗與模擬比較 84
第五章 結論與未來研究方向 86
5.1 結論 86
5.2 未來研究方向 89
參考文獻 90
附錄ASTM D7136 93

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