本文以實驗及理論的方式探討7005-T53鋁合金管在循環彎曲負載下彈塑性力學行為及皺曲損壞之研究。循環彎曲實驗是以『彎管實驗機』及『曲度-橢圓化量測器』對圓管進行實驗，而理論部分是採用內涵時間理論為彈塑性變形的基礎理論，並配合虛功原理來推導必要的的平衡方程式，並利用一組富利葉級數來近似圓管斷面上每一點的位移，從彼此相對應的參數中求得彎曲變形時彎矩、曲度及橢圓化關係。由實驗及理論結果顯示：7005-T53鋁合金管在對稱循環彎曲負載時，會有應變硬化的情形發生；在循環彎曲幾圈後，彎曲力矩與彎曲曲度的迴圈會逐漸趨近於穩定。而管徑會呈現橢圓化的變化，而且隨著循環次數的增加，橢圓化會呈棘齒狀的增加。此外，當控制曲度越大時，圓管發生皺曲破壞的圈數越少；控制曲度越小時，發生皺曲的圈數越多。最後，實驗求得的控制曲度量和到達皺曲的循環次數關係，也將利用1987年Kyriakides與Shaw所提出的理論模式，求得所對應的相關參數。

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