本文係針對 6061-T6鋁合金管在中央無凹槽以及具有尖銳凹槽的情況，控制不同對稱曲度循環彎曲負載至皺曲的試驗。實驗試件係採用無尖銳凹槽(0.0 mm)以及五種不同深度(0.4、0.8、1.2、1.6及2.0 mm)的尖銳凹槽6061-T6鋁合金管，在相同曲度速率下(0.012 m-1/s)進行試驗，以求得橢圓化和循環圈數的關係。
本文發現橢圓化-循環圈數的曲線大致可分成三階段，初始、第二及第三階段，而該曲線的趨勢和Lee et al. 【1】所測試不同尖銳凹槽深度304不鏽鋼管的橢圓化-循環圈數曲線非常相似。最後，本文將Lee et al. 【1】所提的理論模式用來描述起始及第二階段的不同尖銳凹槽深度6061-T6鋁合金圓管橢圓化-循環圈數關係。經與實驗結果比較後發現，理論分析能合理的描述實驗結果。

This paper presents the experimental investigation of the buckling of the 6061-T6 aluminum alloy tube with the unnotched and sharp notch subjected to symmetrical curvature-controlled cyclic bending. There are five different sharp-notched depths (0.4, 0.8, 1.2, 1.6 and 2.0 mm) and unnotched (0.0 mm) of 6061-T6 aluminum alloy tubes. The curvature-rate for the experiment is a constant (0.012 m-1/s) for obtaining the relationship between the ovalization and number of cycles.
It can be observed from the experimental curve of the ovalization - number of cycles curve can divide into three stages, the initial, secondary and tertiary stages. It can be seen that the trend of the curve is similar to that tested by Lee et al. 【1】for 304 stainless steel. Finally, the theoretical model proposed by Lee et al. 【1】is used for simulating the ovalization - number of cycles relationship for 6061-T6 aluminum alloy tubes with different sharp-notched depths in initial and secondary stages. By comparing the theoretical simulation with the experimental data, good agreement between the experimental and theoretical results has been achieved.

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