本文是針對尖銳凹槽深度為0.2、0.4、0.6、0.8及1.0mm的SUS 304不銹鋼圓管進行純彎曲潛變的實驗，以探討其相關的力學行為與皺曲毀損。圓管純彎曲潛變係指圓管被彎曲至某個預設彎矩後，並維持該彎矩一段時間。由實驗結果得知，潛變曲度與橢圓化皆會隨著時間的增加而增加，直至皺曲毀損為止，且在較高的預設彎矩值下，潛變曲度與橢圓化的值增加的較快。最後，本文參考Bailey-Norton的單軸潛變公式後，提出一個可以描述SUS 304不銹鋼圓管在承受純彎曲負載下潛變行為的初始段與第二階段潛變曲度-時間的關係。在經由與實驗數值做比較後發現，理論分析能合理的描述實驗結果。

In this study, the relative mechanical behavior and buckling failure of sharp-notched SUS 304 stainless steel tubes with notch depths of 0.2, 0.4, 0.6, 0.8 and 1.0 mm subjected to pure bending creep are investigated. The pure bending creep is to bend the tube to a desired moment and keep that moment for a period of time. From the experimental result, the creep curvature and ovalization increase with time until the tube buckles. Higher desired moment leads to the higher creep curvature and ovalization. Finally, referring the Bailey-Norton formulation for uniaxial creep, a formulation is proposed for simulating the first and second stages of the creep curvature – time for SUS 304 stainless steel tubes subjected to pure bending creep. Through comparing with the experimental finding, the theoretical analysis can reasonably describe the experimental result.

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