本文使用有限元素ANSYS Workbench 17.0軟體分析不同截面但相同方向多餘圓孔的6061-T6鋁合金圓孔管在循環彎曲負載下的力學行為，其中圓孔管的圓孔位於0o方向(y軸方向)，圓孔直徑固定為6 mm，而所考慮的多餘圓孔位於90o方向(x軸方向)，圓孔直徑固定為2 mm，至於不同截面係指距離圓孔管圓孔的截面有五個不同的水平距離分別為:10、20、30、40與50 mm，所分析的力學行為有：彎矩-曲率關係及橢圓化-曲率關係。
由李永森【18】的實驗結果可看到，改變不同截面的多餘圓孔對彎矩-曲率關係幾乎沒有明顯的影響，且從第一圈循環開始，該曲線即為一穩定迴圈。而橢圓化-曲率關係皆呈現棘齒狀且不對稱的形式成長，且ANSYS分析也能合理的描述李永森【18】所做的實驗結果。一旦確認ANSYS模擬能準確的描述實驗結果，則每一個循環彎曲負載事件中的應力幅度即可準確的求得。由於最大應力及最小應力數值上的並無太大的差異，所以平均應力影響不列入考慮。根據分析結果顯示，所提出的疲勞模式能適當的預測有多餘圓孔的6061-T6圓孔管在循環彎曲負載下的疲勞壽命。

In this study, the finite element ANSYS Workbench 17.0 is used to analyze the mechanical behavior of round-hole 6061-T6 aluminum alloy tubes with a redundant hole on a different cross-section but at the same direction under cyclic bending. The round hole of the round hole tube is in the 0o direction (y-axis direction), and the diameter of the round hole is 6 mm. A redundant hole considered is in the 90o direction (x-axis direction) with a diameter of 2 mm. As for the different cross-section, there are five different sections from the section of the round hole of the round-hole tube. The horizontal distances are 10, 20, 30, 40 and 50 mm. The mechanical behaviors analyzed are moment-curvature relationship and ovalization-curvature relationships.
It can be seen from the experimental results of Y. S. Lee [18] that changing the redundant hole with different cross sections has almost no obvious influence on the moment-curvature relationship. From the first cycle, the moment-curvature relationship shows a stable loop. The ovalization-curvature relationship grows in a ratcheting and asymmetrical form. The ANSYS analysis can reasonably describe the experimental results of Y. S. Lee [18]. Once the ANSYS simulation is confirmed to accurately describe the experimental results, the magnitude of the stress in each cyclic bending load can be accurately determined. Since there is not much difference between the maximum stress and the minimum stress value, the mean stress effect is not considered. According to the analysis results, a proposed fatigue mode can properly predict the fatigue life.

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