本研究利用點應力準則配合ANSYS有限元素軟體，對表層含不同梭織物的混層複合材料平板進行開孔強度之實驗及模擬分析，並預測其開孔破壞強度。點應力準則常用以預測含孔平板強度，近幾年有些學者基於研究結果對點應力準則提出修正。本文首先利用勁度矩陣平均法求得梭織混層複合材料之等效彈性模數，然後代入ANSYS有限元素軟體分析，求得平板之應力分佈。接著以點應力準則求得其特徵長度，並建立特徵長度和孔洞直徑與試片寬度比(D/W)之乘冪關係。此乘冪關係即可預測不同孔徑試片之特徵長度，再利用線性彈性力學之疊加原理即可求出不同孔徑試片之破壞強度，並以實驗值驗證其準確性。結果顯示本研究方法可以準確地預測不同孔徑梭織混層複合材料平板的破壞強度，其誤差介於3%以內。

The aim of this thesis is to simulate, predict and analyze the notched fracture strength of hybrid composite plates with different woven Fabric on the surface layer by Point Stress Criterion and Finite Element Software ANSYS. A modified point stress criterion (PSC) was adopted to predict the strength of notched plate in this study. First, the effective elastic moduli of specimens were predicted by stiffness averaging method. Those moduli were then put into ANSYS for analyzing the stress distribution in the notched plate. The characteristic length of each plate was then figured out by modified PSC, and the power law relationship between the characteristic length and the ratio of hole diameter to specimen width was also established. The characteristic length of different hole diameter can thus be predicted. Employing the theory of superposition in linear elasticity and the predicted characteristic length, the notched strength of woven hybrid composite plates were finally predicted and compared to experimental data. The results indicate that the notched strength of woven hybrid composite plates can be accurately predicted by the methodology in this study, and the error between the predicted value and its corresponding experimental data is within 3 %.

目錄
摘要 i
Abstract ii
圖目錄 vi
表目錄 ix
第一章 緒論 1
1.1 前言 1
1.2 文獻回顧 4
1.3 研究動機與目的 8
1.4 本文章節提要 9
第二章 相關理論 10
2.1 點應力破壞準則 10
2.2 開孔強度預測 12
2.3 梭織混層複合材料之工程模數計算 13
2.4 單位格子設定 14
2.5 單方向複合材料與梭織紗束之工程模數 16
2.6 三維座標轉換 18
2.7 勁度平均法 21
2.8 梭織混層複合材料厚度均質化 22
第三章 實驗 23
3.1 實驗器材 23
3.2 實驗儀器與設備 24
3.3 研究流程 25
3.4 試片製作 27
3.5 金相實驗 28
3.6 拉伸測試 29
3.7 纖維體積含有率計算 32
第四章 電腦輔助工程分析 33
4.1 ANSYS介紹 33
4.2 分析流程 34
4.2.1 前處理器 35
4.2.2 求解器 39
4.2.3 後處理器 40
第五章 結果與討論 41
5.1 開孔加工對不同外觀織物的破壞模式 41
5.1.1 巨觀 41
5.1.2 微觀 42
5.2 開孔試片經拉伸破壞後的破壞模式 45
5.2.1 巨觀 45
5.2.2 微觀 46
5.3 應力分布 48
5.4 孔洞半徑與特徵長度之關係 49
5.5 強度預測 52
5.6 不同紗束K數對梭織混層複合材料平板開孔強度之效應 53
第六章 結論 55

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