篇名 | 局部尖銳凹槽SUS304不鏽鋼管在循環彎曲負載下之力學行為與皺曲損壞 |
---|---|
卷期 | 11:1 |
並列篇名 | Mechanical Behavior and Buckling Failure of Local Sharp-notched SUS304 Stainless Steel Tubes Subjected to Cyclic Bending |
作者 | 李國龍 、 林倩如 、 潘文峰 |
頁次 | 009-019 |
關鍵字 | 局部尖銳凹槽SUS304 不鏽鋼管 、 凹槽深度 、 循環彎曲 、 彎矩 、 曲度 、 橢圓化 、 循環至皺曲圈數 、 有限元素ANSYS分析 、 local sharp-notched SUS304 stainless steel tubes 、 notch depths 、 cyclic bending 、 moment 、 curvature 、 ovalization 、 number of cycles to produce buckling 、 finite element ANSYS analysis |
出刊日期 | 201503 |
本文係針對局部尖銳凹槽深度為0.2、0.4、0.6、0.8、1 mm的SUS304不鏽鋼管,進行曲度控制循環彎曲負載的實驗,以探討其相關的力學行為與皺曲損壞。由實驗彎矩-曲度的關係中發現,隨著循環圈數的增加彎矩值也漸漸的增加,並在經過一些循環曲圈數後該關係會呈現一穩定的迴圈,且凹槽的深度對彎矩-曲度關係幾乎沒有影響。至於橢圓化-曲度關係則隨著循環圈數的增加而呈現棘齒狀的成長,且凹槽的深度越深橢圓化-曲度關係就越不對稱,橢圓化增加也就越大。此外,雖然有五種局部尖銳凹槽的深度,但在雙對數座標的控制曲度-循環至皺曲圈數關係卻呈現五條幾乎平行的直線。最後,本文以有限元素ANSYS來模擬彎矩-曲度及橢圓化-曲度的關係,此外,本文也提出理論模式來描述控制曲度-循環至皺曲圈數的關係。在與實驗結果比較後發現,理論能夠合理描述實驗結果。
In this study, SUS304 stainless steel tubes with local sharp-notched depths of 0.2, 0.4, 0.6, 0.8 and 1 mm were subjected to cyclic bending for investigating relative mechanical behavior and buckling failure. From observing the experimental moment-curvature relationship, when the number of cycles increased, the bending moment also increased. The relationship became a steady loop after several bending cycles. In addition, the notch depth had no influence on the moment-curvature relationship. Regarding the ovalization-curvature relationship, when the number of cycles increased, it exhibited an increased and ratcheted manner. The greater the depth of the notch, the more unsymmetrical the ovalization-curvature relationship became, and the greater the increase of the ovalization. Furthermore, although five local sharp-notched depths were tested, only five nearly parallel lines were observed for the controlled curvature-number of cycles that produced a buckling relationship in the log-log scale. The finite element ANSYS software package was used to simulate the moment-curvature and ovalization-curvature relationships. In addition, this study proposes a theoretical model for simulating the controlled curvature-number of cycles to produce the buckling relationship. Through comparison of the experimental data, the theoretical model could appropriately simulate the experimental findings.