本文給予適當的應力-應變關係、材料模型、網格元素、邊界條件與負載條件，則有限元素分析軟體ANSYS Workbench 19.0可使用來描述不同圓孔直徑的6061-T6鋁合金圓孔管在對稱彎矩控制循環彎曲負載下的力學行為(彎矩－曲率關係和橢圓化－彎矩關係)。本研究共考慮五種不同的圓孔直徑分別為:2、4、6、8與10 mm，五種不同的對稱控制彎矩分別為: 700、 600、 500、 400和 300 N-m。從劉柏佑[16]的實驗結果顯示，從第一圈起彎矩－曲率關係即形成一個迴圈，而隨著循環圈數的增加，迴圈的寬度會漸漸的增加，且對稱控制彎矩越大時，迴圈就越大，圓孔直徑越大時，迴圈就越大，但當對稱控制彎矩太小時，彎矩－曲率關係會呈線性的關係。至於橢圓化-彎矩關係則呈現棘齒、不對稱、蝴蝶結狀的增加趨勢，圓孔直徑越大時，橢圓化就越大，且對稱控制彎矩越大時，橢圓化就越大。最後，有限元素ANSYS分析結果與實驗結果相互比較後可發現，有限元素ANSYS分析可以合理的描述實驗結果。

In this paper, the finite element software ANSYS Workbench 2019 R1 is used to analyze the mechanical response of 6061-T6 aluminum alloy round-hole tubes with hole diameters of 2, 4, 6, 8 and 10 mm subjected to moment-controlled cyclic bending. The mechanical response includes the moment-curvature and ovalization-moment relationships. The controlled symmetrical moments are include: 700、 600、 500、 400, and 300 N-m. According to the experimental result from Liu [16], the moment-curvature relationship shows a loop from the first bending cycle. The width of the loop increases as the number of the bending cycles increases. In addition, a larger controlled moment leads to a larger loop and a larger hole diameter causes a larger loop. When the controlled moment is too small, the moment-curvature relationship becomes linear. As for the ovalization-moment relationship, it presents a ratchetting, asymmetrical, bow-like and increasing trend. In addition, a larger hole diameter causes a larger ovalization and a larger controlled moment leads to a larger ovalization. Finally, by comparison of the ANSYS analysis and the experimental finding, it can be found that the ANSYS analysis can properly simulate the experimental data.

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