臺灣博碩士論文加值系統

本研究利用實驗探討具橢圓孔編織複合材料平板開孔強度的影響，並觀察對其經過拉伸後基材與纖維之間的破壞模式，進一步利用有限元素軟體ANSYS與點應力準則預測各種不同長短軸的橢圓孔編織複合材料平板之破壞強度。首先將碳纖維編織帶含浸環氧樹脂後，以熱壓法製成編織複合材料平板。由金相顯微鏡觀察沿纖維紗束方向的斷面，求得纖維紗數的高長比，並計算纖維體積含有率。帶入撰寫的Visual Basic程式計算編織複合材料之工程模數，再利用勁度矩陣平均法(Stiffness Averaging Method)求得整體編織複合材料平板的材料性質，最後將所得得等校工程模數帶入有限元素軟體ANSYS中進行拉伸分析，得開孔平板的應力分布圖，再配合點應力準則(Point Stress Criterion，PSC)求出特徵長度，並依據線性理論，由特徵長度和孔洞長軸與材料板寬度比值(D/W)呈現乘冪關係計算不同孔徑破壞強度之預測值，並將預測值與實驗值比較。
其結果顯示，本研究方法可以準確預測含有橢圓孔編織複合材料平板之破壞強度，其誤差在4%以內。開孔強度隨著長軸的增加而有下降的趨勢，根據分析結果短軸為5mm的開孔強度略高於短軸為3mm的開孔強度。

致謝 I
摘要 III
ABSTRACT IV
圖目錄 VIII
表目錄 XI
第一章 前言 1
1.1 引言 1
1.3研究動機與目的 8
第二章 原理 9
2.1 點應力破壞準則(POINT STRESS CRITERIA, PSC) 9
2.2材料性質計算 11
2.2.1單位格子 11
2.2.2 單方向複合材料與編織紗束之工程模數 13
2.2.3 三維座標轉換 15
2.2.4 勁度平均法 17
2.3 利用基於有限元素法之點應力破壞準則預測開孔強度 18

第三章 實驗 19
3.1 實驗材料: 19
3.2 實驗儀器: 21
3.3 研究流程 22
3.4 試片製作 24
3.5 體積含有率計算 32
3.6金相實驗 33
3.7 編織複合材料平板之材料性質測試 36
3.8 拉伸實驗 37
3.9試片開孔加工 40
第四章 有限元素軟體分析 41
4.1 有限元素法ANSYS介紹 41
4.2 前處理 44
4.2.2　求解器 45
4.2.3　後處理 48
第五章 結果與討論 49
5.1　編織複合材料之材料性質驗證 49
5.2　破壞模式 50
5.2.1　巨觀破壞模式 50
5.2.2　微觀破壞模式 52
5.3　應力分布 54
5.4　孔洞半徑與特徵長度之關係 56
5.5　強度預測 60
5.6 橢圓孔長短比的差別對編織複合材料平板開孔強度效應 63
第六章 結論 66
參考文獻 68

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