本研究是以有限元素分析軟體ANSYS Workbench 15.0分析具有不同深度局部圓形凹痕之6061-T6鋁合金圓管，承受對稱循環彎曲負載時凹痕的變形。其中凹痕深度有0.3、0.6、0.9和1.2 mm，而循環彎曲的曲度控制在±0.35 m^(-1)之間。所分析的循環圈數有第1、5、10和15圈的凹痕變化，並將正向最大曲度凹痕最深位置的數值和反向最大曲度凹痕最深位置的數值相減，可得到上述循環圈數中凹痕變形的總變化量。有限元素分析計算的結果和韓宗儒【17】實驗拍攝的照片並經影像處理後的結果做比較發現，在第一圈時，不同曲度位置凹痕深度數值都不相同，但第五圈之後凹痕呈現穩定變動，且隨著循環圈數越多凹痕變形的變化量有越來越小的趨勢，雖然分析數值與實驗值仍有些許的差異，但趨勢上都非常相似。

In this study, the finite element software ANSYS Workbench 15.0 is used to analyze the deformation of local round-dented 6061-T6 aluminum tubes under curvature-controlled cyclic bending. Different notch depths include 0.3, 0.6, 0.9 and 1.2 mm. The controlled curvature of the cyclic bending is  0.35 m-1. The deformations of the dent are analyzed at the first, fifth, tenth and fifteenth cycles. The deepest location of the dent at the positive maximum curvature subtracts the deepest location of the dent at the negative maximum curvature, thus, the total deformation of the dent deformation at that cycle can be obtained. When the finite element analysis result compares with the experimental image processing photographs shot by Han [17], the amounts of the dent depth are different along with the different curvature at the first cycle. But the dent deformation exhibits steady change at the fifth cycle. After a few bending cycles, the deformation of dent shows gradual decreasing phenomenon. Although some differences between the ANSYS analysis and experimental image processing photographs are found, but the trends of curves are similar.

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