本文主要在撰寫一套以Visual Basic 6.0撰寫的系統，並連結其他輔助軟體ANSYS 與MATLAB，來進行金屬材料疲勞破壞分析。主要目標是提供很容易上手的介面，透過視窗對話方式進行，程式透過介面接收使用者指令，配合輔助軟體進行計算，將分析結果輸出為本系統的目標。
分析對象主要針對於船舶常用之鋼鐵材料、鋁合金材料。本文建立了S-N 法的壽命預估與裂縫進展兩種分析項目。在裂縫進展項目中，包含了貫穿裂縫、1/4 橢圓表面裂縫與1/2 橢圓表面裂縫形式。負荷形式方面，提供規則荷重、亂形荷重、暴風模式三種形式選擇。亂形荷重使用反函數法產生再利用雨滴法做歸納統計。暴風模式採用統計資料，得到不同暴風等級其波浪作用次數和力量大小。
材料參數輸入方面，S-N法採用兩種輸入1.將實驗數據利用最小二乘方法作線性迴歸計算，求出一條適合直線方程式作預估2.已知 或 參數情況下由文獻計算出相關參數作預估。裂縫進展採用輸入裂縫長度、材料性質C、m值、應力強度因子K帶入Paris Law來作預估，當使用者不知材料性質C、m值時本程式提供由材料種類選擇作決定，或將實驗數據da/dN、△K利用最小二乘方法求得。
應力集中部分利用ANSYS得到應力集中係數Kt配合應力強度修正因子Ma預估受應力集中時的裂縫進展。暴風模式對銲接構件造成的累積損害本文利用Miner的方法做損傷累計。
最後將計算結果跟文獻對照本程式預估的準確性，對本程式的整體功能做個結論。

This text is written about the system with the Visual Basic 6.0 and link the other auxiliary software ANSYS and MATLAB to analyze the fatigue fracture of the metal material. The main purpose is to offer the very simple interface to user. Talking through the window and receiving the order of the user by the interface, and cooperating with the auxiliary software for the calculation could output the analyzed result which is the goal of this system.
The analytic target is the common steel material or aluminum alloy material of the ship building. We set up the two kinds of analytic projects that are the S-N law and the crack growth in this text. In the project of crack growth, it includes the through crack, the quarter-elliptical surface cracks, and the semi-elliptical surface crack. In load shape, it has three kinds of forms to choose. It includes the regular loading, the random loading, and the storm model. First, the random loading applies the inverse function and reuses the Rainflow Counting to generalize the statistics. Then, the storm model adopts the statistical data to receive the different storm winds of the grades, the cycles of the wave actions, and the size of the strength.
In part of the material parameter inputs, the S-N law adopts two kinds of ways. 1. Utilizing the Least-square method to do the linear regression of experiment data. It figures out one fitting linear equation for the estimation. 2. To have the known parameter or , it calculates the relevant parameter of the computations from the reference. The Crack grown uses the length of crack, the material property C & m value, and the stress intensity factor K into the Paris Law figure. When the user unknown the C & m value of the material property, this program gives the user to choose the decision by the material type, or utilizing the Least-square method to get of da/dN &△K data.
The stress concentration utilizes the ANSYS analysis to get the stress concentration factor Kt and cooperates with the stress intensity factor Ma to estimate the crack growth under the surface material of the stress concentration. Concerning the damage summing of the weld component in the storm model, we utilized the method of Miner.
Finally, we contrast the program result with the references for the accuracy of the estimation and make the conclusion of this program function.

[1] A. Wöhler, “Uber die Festigkeitversuche mit Eisen und Stahl”, Zeitsc-hrift fur Bauwesen, Vol. VIII, X, XIII, XVI, and XX, 1860/70. English account of this work is in Engineering, 11, 1871.

[2] C.H. Lin and C.F. Zhan, “The Stress Concentration Effect on the Propagating Behavior of Surface Cracks”, Journal of Taiwan Society of Naval Architects and Marine Engineers, Vol.24, No.4, pp.233-239, 2005.

[3] Elber, Wolf, “The Significance of Fatigue Crack Close”, ASTM STP 486, pp230-242, 1971.

[4] “Fatigue Strength Analysis for Mobile Offshore Units”, DET NORSKE VERITAS (DNV), pp20-23, 1984.

[5] G. R. Irwin, “Analysis of Stresses and Strains near the End of a Crack Traversing a Plate”, Trans. ASME, J. Appl. Mech., Vol. E24, p.361, 1957.

[6] H. J. Cough, “The Fatigue of Metals”, Scott, Greenwood and Son, London,1926.

[7] J. C. Newman, Jr. and I. S. Raju, “Stress Intensity Factor Equations for Crack in Three-Dimensional Finite Bodies”, NASA Technical Memorandom 83200 , pp.1-49, 1981.

[8] Julie A. Bannantine, Jess J. Comer, James L. Handrock, “Fundamentals of Metal Fatigue Analysis”, Prentice Hall, Englewood Cliffs, New Jersey , 1990.

[9] M. A. Miner, “Cumulative Damage in Fatigue”, J. Appl. Mech., Val.12, Trans. ASME, Vol.67 , pp.A159-A164, 1945.

[10] M. Matsuishi and T. Endo, “Fatigue of Metals Subjected to Varying Stress”, paper presented to Japan Society of Mechanical Engineers, Fukuoka, Japan, March 1968.

[11] P. C. Paris and F. Erdogan “A Critical Analysis of Crack Propagation Laws”, Trans. ASME, J. Basic Eng. ,Vol. D85,pp.528-534,1963.

[12] Sunder R, Seetharam S A, Bhaskaran T A. “Cycle Counting for Fatigue Crack Analysis”. Int. J Fatigue, 6(3):147~156, 1984.

[13] Y. Murakami, “Stress Intensity Factor Handbook”, The Society of Material Science, Japan , pp.712-722,1987.

[14] ZHU Yi Gang, “Damage Counting Algorithm for Random Load Fatigue Analysis”, Journal of Mechanical Strength, 26(s):032~035,2004.
[15]林忠宏,“破壞力學に基づく溶接構造物の疲勞設計に關する研究”.

[16]岡村弘之,線性破壞力學入門,培風館,1976.

[17]黃聖文, “船用鋁合金板A5083P-O疲勞裂縫進展之研究”,國立成功大學造船暨船舶機械工程研究所碩士論文,1997.

[18]詹奇峰, “應力集中效應對表面疲勞裂縫之影響”,國立成功大學造船暨船舶機械工程研究所碩士論文,2003.