本文主要針對五種不同尖銳凹槽深度的SUS304不銹鋼管做對稱循環彎曲負載實驗，以探討其力學行為與皺曲損壞的關係。實驗係透過彎管試驗機與曲度-橢圓化量測器來進行實驗數據的控制、量測及蒐集。從實驗彎矩－曲度曲線圖中顯示出，在控制曲度做循環彎曲負載時，實驗試件皆有循環硬化的現象產生，且經過反覆的加載與卸載行為後，其迴圈會漸趨於穩定。其次，由實驗橢圓化－曲度的曲線圖發現，橢圓化值會隨著循環彎曲的圈數增加而成棘齒狀的增加，且當橢圓化值增加到某一臨界值時，圓管便會發生皺曲損壞。此外，由實驗曲度－循環圈數的關係圖可看出，控制的曲度越大時，循環圈數就越小。若將上述實驗值置於雙對數座標中，發現五個不同尖銳凹槽深度的試件其上述關係可近似為五條幾乎平行的直線。最後，參考Shaw 和 Kyriakides【2】、Lee等人【11】與陳立銓【17】論文中所提出的理論方程式，並導入尖銳凹槽深度後提出一個可以描述不同尖銳凹槽深度薄壁管在循環彎曲負載時，控制曲度與循環彎曲皺曲圈數關係的理論方程式。在與實驗值做比較後發現，理論分析能充分的描述實驗結果。

This thesis investigates the mechanical behavior and buckling failure of SUS 304 stainless steel tubes with five different sharp-notched lengths subjected to symmetric cycling bending. The tube bending machine and curvature-ovalization measurement apparatus was used to control, measure and collect the experimental data. It can be observed from the experimental moment-curvature curve that the tube exhibits cyclical hardening during the symmetric cycling bending and becomes steady after a few cycles. Next, for the experimental ovalization-curvature curve, the ovalization of the tube cross-section increases in a ratcheting manner with the number of cycles. When the tube ovalization reaches to a critical amount, the tube buckles. In addition, it is shown in the experimental curvature-number of cycles curve that the larger control curvature leads to a fewer amount of the number of cycles. If the aforementioned experimental data plot in a log-log scale, five almost parallel straight lines can be found for five different sharp-notched lengths. Finally, by referring the theoretical formulations proposed by Shaw and Kyriakides【2】, Lee et al.【11】and Chen【17】and including the factor of the sharp-notched lengths, a theoretical formulation was proposed to simulate the relationship between the controlled curvature and the number of cycles to produce buckling. By comparing the theoretical analysis with the experimental data, it is shown that the theoretical formulation can properly simulate the experimental results.

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16.陳信嘉，2006，「不同內直徑及外直徑SUS 304不銹鋼管在循環彎曲負載下力學行為及皺曲損壞之實驗分析」，國立成功大學工程科學研究所碩士論文。

17.陳立銓，2007，「不同內外直徑圓管在循環彎曲負載下力學行為及皺曲損壞之分析」，國立成功大學工程科學研究所碩士論文。